Bihar STET Computer Science Question Paper 7 November 2025 (Shift 1) with Answers

Looking for the Bihar STET Computer Science question paper 2025? Here is the complete Paper II (Class 11-12) Computer Science paper of the exam held on 7 November 2025 (Shift 1), with the correct answer and a short explanation for every question. All 150 questions are given as text, so you can practise them online, revise topic by topic and get a feel for the real exam pattern.

Note: These answers were prepared and checked by the ExamYaari team. They are not the official BSEB answer key. If you think an answer is wrong, tell us in the comments.

हिंदी में पढ़ें: बिहार STET कंप्यूटर साइंस प्रश्न पत्र 7 नवंबर 2025 (शिफ्ट 1) हिंदी में

Table of Contents

• Exam Overview
• Topic-wise Analysis
• Part I: Computer Science (Q1–100)
• Part II: Teaching Aptitude (Q101–130)
• Part III: General Awareness & Reasoning (Q131–150)
• More Bihar STET Computer Science Papers
• FAQs

Bihar STET Computer Science 2025: Exam Overview

Exam	Bihar STET 2025 (Secondary Teacher Eligibility Test)
Conducting Body	Bihar School Examination Board (BSEB)
Paper	Paper II (Class 11-12), Computer Science (Subject Code 226)
Exam Date	7 November 2025
Shift / Time	Shift 1 (9:00 AM – 11:30 AM)
Total Questions	150 MCQs
Part 1	Part I: Computer Science: Q1–100
Part 2	Part II: Teaching Aptitude: Q101–130
Part 3	Part III: General Awareness & Reasoning: Q131–150

Topic-wise Analysis of Computer Science Questions

Here is roughly how the 100 Computer Science questions in this paper are spread across the syllabus. Use it to decide which topics to revise first.

Topic	No. of Questions
Computer Networks & Internet	17
Data Structures & Algorithms	13
Digital Electronics & COA	10
Other Topics	9
Database & SQL	9
Operating System	8
OOP Concepts	7
Python Programming	5
Theory of Computation	4
IoT & Emerging Tech	4
E-commerce & IT Fundamentals	3
Web Technology & HTML	3
Computer Fundamentals & History	2
Software Engineering	2
Cyber Security & Ethics	2
Image Processing & Multimedia	1
Artificial Intelligence	1

Part I: Computer Science (Q1–100)

Q1. If a robot is able to change its own trajectory as per the external conditions, then the robot is considered as the_

(A) Intelligent
(B) Open loop
(C) Mobile
(D) Non-servo

Answer: (A) Intelligent
Explanation: A robot that senses its surroundings and changes its own path on its own is called an intelligent robot.

Q2. Convert the Boolean function F(A, B, C) = Π(0, 2, 4, 5, 7) to its simplified POS form

(A) A + B + C
(B) A + B’ + C
(C) A’B’C’
(D) (A + B)(A + C’)(B + C)

Answer: (D) (A + B)(A + C’)(B + C)
Explanation: Maxterms 0,2,4,5,7 actually simplify to (A+C)(A′+B)(A′+C′), which matches none of the options exactly. D is the only option written as a product of sums, so it is the closest.

Q3. Which keyword is used to define an abstract method within an abstract class?

(A) abstract
(B) virtual
(C) override
(D) implement

Answer: (A) abstract
Explanation: In languages such as Java, an abstract method is declared with the ‘abstract’ keyword and has no body.

Q4. The Floyd-Warshall algorithm is a popular method for solving the All-Pair Shortest Paths problem. What is the time complexity of the Floyd-Warshall algorithm for a graph with “n” vertices?

(A) O(n)
(B) O(n log n)
(C) O(n^2)
(D) O(n^3)

Answer: (D) O(n^3)
Explanation: Floyd-Warshall uses three nested loops over the n vertices, giving O(n³).

Q5. Which of the following applications include in the Strategic Computing Program?

(A) Battle Management
(B) Autonomous systems
(C) Pilot’s associate
(D) All of the above

Answer: (D) All of the above
Explanation: DARPA’s Strategic Computing Program covered battle management, autonomous vehicles and the pilot’s associate.

Q6. Turing machine can be represented using:

(A) Transition table
(B) Transition diagram
(C) Instantaneous description
(D) All of these

Answer: (D) All of these
Explanation: A Turing machine can be described by a transition table, a transition diagram or instantaneous descriptions.

Q7. All of the following are considered biometrics, except:

(A) Fingerprint
(B) Password
(C) Voice
(D) Retina

Answer: (B) Password
Explanation: Biometrics use physical or behavioural traits (fingerprint, voice, retina); a password is knowledge-based.

Q8. To which of the following the term “DBA” referred?

(A) Data Bank Administrator
(B) Database Administrator
(C) Data Administrator
(D) None of the above

Answer: (B) Database Administrator
Explanation: DBA stands for Database Administrator, the person who manages a database.

Q9. The default baud rate of Modbus RTU is?

(A) 19600
(B) 19200
(C) 38400
(D) 57600

Answer: (B) 19200
Explanation: 19200 bps is the commonly used default baud rate for Modbus RTU. (19600 is not a standard rate.)

Q10. The goal of synchronization mechanisms in parallel programming is to:

(A) Speed up the execution of processes
(B) Eliminate parallelism
(C) Avoid deadlock situations
(D) Increase the number of race conditions

Answer: (C) Avoid deadlock situations
Explanation: Synchronization coordinates processes to prevent race conditions and deadlocks; of the options, avoiding deadlock is the correct goal.

Q11. Which of the following IP addresses is valid

(A) 122.94.96.212
(B) 212.254.258.210
(C) 210.10.12.156.209
(D) 122.294.56.68

Answer: (A) 122.94.96.212
Explanation: Each octet of an IPv4 address must be 0–255 and there must be exactly four octets; only 122.94.96.212 meets both rules.

Q12. ___________ plot is used to show the spread and centers of a dataset.

(A) box
(B) line
(C) bar
(D) histogram

Answer: (A) box
Explanation: A box plot shows the median (centre) and the spread (quartiles, range) of data.

Q13. How can you establish a connection between PHP and MySQL?

(A) Using the “connect()” function in PHP
(B) By including a PHP library
(C) By embedding MySQL queries directly in PHP code
(D) By using the “mysqli_connect()” function in PHP

Answer: (D) By using the “mysqli_connect()” function in PHP
Explanation: mysqli_connect() (or PDO) opens a connection from PHP to a MySQL server.

Q14. Which one is not a physical threat

(A) Hacking
(B) Storm
(C) Fire
(D) Flood

Answer: (A) Hacking
Explanation: Hacking is a logical (cyber) threat; storms, fire and floods are physical threats.

Q15. The SQL keyword……………….is used with wildcards.

(A) LIKE
(B) IN
(C) NOT IN
(D) DISTINCT

Answer: (A) LIKE
Explanation: LIKE is used with the wildcards % and _ for pattern matching.

Q16. What is the key advantage of using a carry-lookahead adder instead of a ripple-carry adder?

(A) Simplicity of design
(B) Faster propagation delay
(C) Lower power consumption
(D) Reduced gate count

Answer: (B) Faster propagation delay
Explanation: A carry-lookahead adder computes carries in advance, so it avoids the slow ripple of the carry and has a smaller delay.

Q17. What is the difference between a hard disk drive and a solid-state drive?

(A) A hard disk drive uses spinning disks to store data, while a solid-state drive uses flash memory to store data.
(B) A hard disk drive is slower than a solid-state drive.
(C) A hard disk drive is more durable than a solid-state drive.
(D) All of the above

Answer: (A) A hard disk drive uses spinning disks to store data, while a solid-state drive uses flash memory to store data.
Explanation: An HDD stores data on spinning magnetic platters while an SSD uses flash memory. (SSDs are actually more durable, so ‘All of the above’ is wrong.)

Q18. In an operating system, a “buffer cache” is used to:

(A) Store files in memory
(B) Store copies of frequently used files in memory
(C) Store the operating system kernel
(D) Store input/output devices

Answer: (B) Store copies of frequently used files in memory
Explanation: The buffer cache keeps copies of frequently used disk blocks in RAM to speed up I/O.

Q19. ___________________ are the set of rules that governs how data can be transmitted over world wide web.

(A) Hyper Text Transfer Protocol
(B) Encryption Standards
(C) Cyber forensic
(D) Digital Certificates

Answer: (A) Hyper Text Transfer Protocol
Explanation: HTTP is the set of rules for transferring data over the World Wide Web.

Q20. Multimedia system require hard real time scheduling ___________

(A) to ensure critical tasks will be serviced within timing deadlines
(B) to deliver the media file to the client
(C) to minimize the delay
(D) for security

Answer: (A) to ensure critical tasks will be serviced within timing deadlines
Explanation: Audio and video playback has strict deadlines, so hard real-time scheduling makes sure critical tasks finish in time.

Q21. Which of the following applications is a typical use of microcontrollers in the field of home automation?

(A) Satellite communication
(B) Air traffic control
(C) Temperature and lighting control
(D) Space exploration

Answer: (C) Temperature and lighting control
Explanation: Home automation uses microcontrollers to control temperature, lighting and appliances.

Q22. What is the purpose of SQL injection attacks?

(A) To increase the performance of database queries
(B) To bypass authentication systems
(C) To improve database security
(D) To enhance data encryption

Answer: (B) To bypass authentication systems
Explanation: SQL injection inserts malicious SQL into input fields to bypass logins or read and modify data.

Q23. What is the primary purpose of data compression in data communication?

(A) To increase latency
(B) To reduce bandwidth usage
(C) To decrease error rates
(D) To improve security

Answer: (B) To reduce bandwidth usage
Explanation: Compression reduces the amount of data sent, which saves bandwidth.

Q24. What is the term for a variable that references an instance of a class?

(A) Property
(B) Method
(C) Object
(D) Constructor

Answer: (C) Object
Explanation: A variable that refers to an instance of a class is an object (an object reference).

Q25. Which network device serves as the entry and exit point of a network, as all data coming in or going out of a network must first pass through it?

(A) Modem
(B) Gateway
(C) Switch
(D) Repeater

Answer: (B) Gateway
Explanation: A gateway is the entry and exit point of a network and connects it to other networks.

Q26. Identify the correct output of the following code snippet:

game = "olympic2024"
print(game.index("C"))

(A) 0
(B) 6
(C) -1
(D) valueError

Answer: (D) valueError
Explanation: Python strings are case-sensitive; uppercase ‘C’ does not occur in ‘olympic2024’, so index() raises ValueError.

Q27. In a B tree of order m, each internal node can have up to __ children.

(A) m – 1
(B) m
(C) 2m – 1
(D) 2m

Answer: (B) m
Explanation: In a B-tree of order m, a node can have at most m children (and m − 1 keys).

Q28. Which of the following is the correct expansion of SMS ?

(A) Short Message Service
(B) Small Multimedia Service
(C) Short Multimedia Service
(D) Small Message Service

Answer: (A) Short Message Service
Explanation: SMS stands for Short Message Service.

Q29. Which of the following statement (s) is/are TRUE in respect of Media Access Control (MAC) Address? (A) It can be changed if a node is removed from one network and connected to another network. (B) Each MAC address is a 12-digit hexadecimal number. (C) It is a unique value associated with a network adapter called NIC. (D) It is provided by the Internet Service Provider to locate computers connected to the internet. Choose the correct answer from the options given below:

(A) (B) and (C) only
(B) (A), (B) and (C) only
(C) (C) and (D) only
(D) (A) and (B) only

Answer: (A) (B) and (C) only
Explanation: A MAC address is a 12-digit hexadecimal number burned into the NIC. It does not change when the node moves to another network and is not given by the ISP.

Q30. While creating a table, which constraint does not allow insertion of duplicate values in the table ?

(A) UNIQUE
(B) DISTINCT
(C) NOT NULL
(D) HAVING

Answer: (A) UNIQUE
Explanation: The UNIQUE constraint stops duplicate values from being inserted into a column.

Q31. Which term is used to describe the ability of different classes to be treated as objects of the same parent class?

(A) Overloading
(B) Polymorphism
(C) Abstraction
(D) Encapsulation

Answer: (B) Polymorphism
Explanation: Polymorphism lets objects of different subclasses be treated as objects of a common parent class.

Q32. Building blocks of a frame structure are?

(A) Facts and Data
(B) Procedure and Default values
(C) Frame names
(D) Frame inference in hierarchy

Answer: (A) Facts and Data
Explanation: A frame is made of slots that hold facts and data (plus attached procedures and default values).

Q33. Segmentation is a memory management technique where memory is divided into segments, with each segment containing:

(A) Fixed-sized blocks of memory
(B) Different types of data structures
(C) Variable-sized blocks of memory
(D) Non-contiguous blocks of memory

Answer: (C) Variable-sized blocks of memory
Explanation: Segments are logical units (code, data, stack) of different sizes, i.e. variable-sized blocks.

Q34. About IoT, which among the followings is not correct?

(A) Light sensor is analog
(B) microphone is a digital sensor
(C) Keyboard is a digital sensor
(D) Push button is a digital Sensor

Answer: (B) microphone is a digital sensor
Explanation: A microphone produces a continuously varying analog signal, so calling it a digital sensor is wrong.

Q35. Connected components in a graph can be found using which graph traversal algorithm?

(A) DFS
(B) BFS
(C) Both DFS and BFS
(D) Neither DFS nor BFS

Answer: (C) Both DFS and BFS
Explanation: Both DFS and BFS can find connected components; each traversal from an unvisited vertex finds one component.

Q36. A complex SCADA system has _______levels?

(A) 6
(B) 5
(C) 3
(D) 4

Answer: (B) 5
Explanation: A complex SCADA system is usually described in 5 levels (Level 0 field devices up to Level 4 production scheduling).

Q37. Hierarchical addressing in the Network Layer allows for:

(A) More efficient use of IP addresses
(B) Dynamic allocation of MAC addresses
(C) Faster data transmission rates
(D) Reduced latency in data communication

Answer: (A) More efficient use of IP addresses
Explanation: Hierarchical (network/host) addressing allows route aggregation and more efficient use of IP addresses.

Q38. According to Chomsky hierarchy, which of the following is recognized by Recursively Enumerable language?

(A) Type 0
(B) Type 1
(C) Type 2
(D) Type 3

Answer: (A) Type 0
Explanation: Recursively enumerable languages are Type 0 in the Chomsky hierarchy and are recognised by Turing machines.

Q39. Which SQL clause is used to retrieve specific rows from a table?

(A) SEARCH
(B) FETCH
(C) SELECT
(D) FIND

Answer: (C) SELECT
Explanation: SELECT retrieves data from a table; it is combined with WHERE to pick specific rows.

Q40. In conditional asymptotic notation, “Θ(f(n)) if g(n)” indicates that the algorithm’s complexity is both upper and lower bounded by f(n) when:

(A) g(n) is a lower bound on f(n)
(B) g(n) is an upper bound on f(n)
(C) g(n) is true
(D) g(n) is false

Answer: (C) g(n) is true
Explanation: Conditional asymptotic notation means the bound Θ(f(n)) holds only for those n where the condition g(n) is true.

Q41. The OSI model consists of how many layers?

(A) 5
(B) 6
(C) 7
(D) 8

Answer: (C) 7
Explanation: The OSI model has 7 layers.

Q42. In a relational database, what is a primary key?

(A) A key used for opening encrypted data
(B) A unique identifier for a record in a table
(C) A foreign key from another table
(D) An index for sorting data

Answer: (B) A unique identifier for a record in a table
Explanation: A primary key uniquely identifies each record (row) in a table.

Q43. What will be the output of the following code segment?

a = 5
def func_1(b=10):
    global a
    a = b - 10
    b += a
    print(a, b)

func_1(a)

(A) 0 5
(B) 5 0
(C) 0 -5
(D) -5 0

Answer: (D) -5 0
Explanation: Calling func_1(5) sets the global a = 5 − 10 = −5; then b = 5 + (−5) = 0. Output: -5 0.

Q44. Which JavaScript method is used to add a new HTML element to the DOM?

(A) appendElement()
(B) createElement()
(C) newElement()
(D) addElement()

Answer: (B) createElement()
Explanation: document.createElement() creates a new element, which is then added to the page with appendChild().

Q45. The primary function of firewall in network security is

(A) To monitor network traffic and detect anomalies.
(B) To create virtual private networks for secure communication.
(C) To filter incoming and outgoing network traffic based on security rules
(D) To encrypt data before Transmission.

Answer: (C) To filter incoming and outgoing network traffic based on security rules
Explanation: A firewall filters incoming and outgoing traffic according to security rules.

Q46. In AI systems, Knowledge can be represented in two ways. What are these two ways? (i) Machine Logic (ii) Predicate Logic (iii) Propositional Logic (iv) Compound Logic

(A) (i) and (ii)
(B) (i) and (iii)
(C) (ii) and (iii)
(D) (iii) and (vi)

Answer: (C) (ii) and (iii)
Explanation: Knowledge in AI is mainly represented using propositional logic and predicate (first-order) logic.

Q47. What is the difference between a URL and a web address?

(A) A URL is a Uniform Resource Locator, while a web address is away to identify a website on the internet.
(B) A URL is a software program, while a web address is ahardware device.
(C) A URL is a physical object, while a web address is a logicalobject.
(D) All of the above.

Answer: (A) A URL is a Uniform Resource Locator, while a web address is away to identify a website on the internet.
Explanation: A URL is the full address of a resource; ‘web address’ is the everyday term for the address of a website.

Q48. Monitors are primarily used for achieving:

(A) Deadlocks
(B) Starvation
(C) Mutual exclusion and synchronization
(D) Process termination

Answer: (C) Mutual exclusion and synchronization
Explanation: A monitor is a high-level construct that provides mutual exclusion and synchronization.

Q49. In EDI, I stands for?

(A) Indian
(B) India
(C) Interchange
(D) Interval

Answer: (C) Interchange
Explanation: EDI = Electronic Data Interchange.

Q50. Which protocol provides connectionless communication with minimal overhead?

(A) TCP
(B) UDP
(C) IP
(D) HTTP

Answer: (B) UDP
Explanation: UDP is connectionless and has very low overhead (no handshake or acknowledgements).

Q51. Which maintenance activity involves updating software to work with new hardware or software environments?

(A) Corrective Maintenance
(B) Adaptive Maintenance
(C) Perfective Maintenance
(D) Preventive Maintenance

Answer: (B) Adaptive Maintenance
Explanation: Adaptive maintenance changes software so it works in new hardware or software environments.

Q52. A formal model of protection in an operating system provides:

(A) A mathematical framework for analyzing resource allocation
(B) Guidelines for designing user interfaces
(C) Methods for optimizing memory management
(D) Techniques for improving CPU utilization

Answer: (A) A mathematical framework for analyzing resource allocation
Explanation: A formal protection model (such as the access matrix) gives a mathematical framework for analysing access to resources.

Q53. minimum number of states required to recognize an octal number divisible by 3 are/is

(A) 3
(B) 4
(C) 1
(D) 2

Answer: (A) 3
Explanation: Only the remainder mod 3 (0, 1 or 2) needs to be tracked, so a DFA needs 3 states.

Q54. Which command is used to remove a relation from an SQL?

(A) Drop table
(B) Delete
(C) Purge
(D) Remove

Answer: (A) Drop table
Explanation: DROP TABLE removes the whole relation (structure and data); DELETE only removes rows.

Q55. What does the term “Software Maintenance” refer to?

(A) Developing new software applications
(B) Enhancing software performance
(C) Managing hardware components
(D) Modifying and updating existing software

Answer: (D) Modifying and updating existing software
Explanation: Software maintenance means modifying and updating existing software after delivery.

Q56. The recurrence equation T(n) = T(n/2) + T(n/3) + n represents the time complexity of which algorithmic paradigm?

(A) Divide and Conquer
(B) Dynamic Programming
(C) Greedy Algorithms
(D) Backtracking

Answer: (A) Divide and Conquer
Explanation: The problem is split into subproblems of size n/2 and n/3 and the results are combined in O(n) time, which is divide and conquer.

Q57. What does the term “harvard architecture” refer to in the context of microcontrollers?

(A) A type of microcontroller with high processing speed
(B) A microcontroller architecture that uses a separate memory space for instructions and data
(C) A microcontroller with advanced addressing modes
(D) A microcontroller with a large number of I/O ports

Answer: (B) A microcontroller architecture that uses a separate memory space for instructions and data
Explanation: Harvard architecture uses separate memories and buses for instructions and data.

Q58. Consider the statements given below and then choose the correct output from the given options:

L = ['TIC', 'TAC']
print(L[::-1])

(A) [‘CIT’ , ‘CAT’ ]
(B) [‘TIC’ , ‘TAC’ ]
(C) [‘CAT’ , ‘CIT’ ]
(D) [‘TAC’ , ‘TIC’ ]

Answer: (D) [‘TAC’ , ‘TIC’ ]
Explanation: L[::-1] reverses the list order (not the strings): [‘TAC’, ‘TIC’].

Q59. Which of the following is not an attribute of the <font> tag?

(A) face
(B) height
(C) size
(D) colour

Answer: (B) height
Explanation: The <font> tag supports face, size and color; height is not one of its attributes.

Q60. The term “multi-user” in an OS context refers to:

(A) An OS that can execute multiple programs simultaneously
(B) An OS that supports multiple users working on the same machine
(C) An OS that can only run on multiple computers
(D) An OS with a graphical user interface

Answer: (B) An OS that supports multiple users working on the same machine
Explanation: A multi-user OS lets several users use the same computer system at the same time.

Q61. TPDU (Transport Protocol Data Unit) refers to:

(A) A unit of data in the physical layer
(B) A unit of data in the data link layer
(C) A unit of data in the transport layer
(D) A unit of data in the network layer

Answer: (C) A unit of data in the transport layer
Explanation: A TPDU is the data unit exchanged at the transport layer (a segment).

Q62. A* search algorithm is based on?

(A) BFS
(B) DFS
(C) Uniform cost search
(D) Best first Search

Answer: (D) Best first Search
Explanation: A* is a best-first search that uses f(n) = g(n) + h(n).

Q63. What is the primary purpose of using Don’t Care conditions in Karnaugh Map simplification?

(A) To mark cells that should not be included in the simplification process
(B) To indicate cells that have an undefined logic value
(C) To identify cells that are already in their simplest form
(D) To mark cells with special logic functions

Answer: (B) To indicate cells that have an undefined logic value
Explanation: A don’t-care cell’s output is unspecified, so it can be treated as 0 or 1, whichever makes the groups larger.

Q64. Which among the followins is not a type of Zigbee Device?

(A) Zigbee Coordinator device
(B) Zigbee Router
(C) Zigbee start devce
(D) Zigbee end devce

Answer: (C) Zigbee start devce
Explanation: ZigBee devices are the Coordinator, Router and End Device; there is no ‘start device’.

Q65. Zigbee is a task group in______

(A) LAN
(B) PAN
(C) MAN
(D) WAN

Answer: (B) PAN
Explanation: ZigBee (IEEE 802.15.4) is a wireless personal area network (PAN) standard.

Q66. In a threaded binary tree, the space required for threads is usually:

(A) Greater than the space required for regular pointers
(B) Equal to the space required for regular pointers
(C) Less than the space required for regular pointers
(D) Unpredictable

Answer: (B) Equal to the space required for regular pointers
Explanation: Threads reuse the NULL child pointer fields, so they take the same space as ordinary pointers (plus a small flag bit).

Q67. Given the Boolean expression F(A, B, C, D) = Σ(0, 1, 2, 3, 8, 9, 10, 11), what is the simplified expression using the algebraic method?

(A) A + B + C + D
(B) AB + AC + AD + BC + BD + CD
(C) AB + CD
(D) A’BC’D + ABC’D + A’BCD + ABCD

Answer: (C) AB + CD
Explanation: Minterms 0–3 and 8–11 are exactly the cells where B = 0, so F = B′. None of the options is correct; check against the official key.

Q68. Which model considers risk assessment and incremental development in software projects?

(A) Waterfall Model
(B) Agile Model
(C) Prototype Model
(D) Spiral Model

Answer: (D) Spiral Model
Explanation: The Spiral model combines incremental development with risk analysis in every loop.

Q69. Which of the following expression in SQL would calculate the square root of 16?

(A) POWER (16,2)
(B) POWER (16, 0.5)
(C) POWER (16, 1)
(D) MOD (16)

Answer: (B) POWER (16, 0.5)
Explanation: POWER(16, 0.5) = 16^½ = 4, the square root.

Q70. A relation in a relational database is also known as:

(A) A data type
(B) An attribute
(C) A schema
(D) A table

Answer: (D) A table
Explanation: In the relational model, a relation is a table.

Q71. A Database Management System is a type of _________software.

(A) It is a type of system software
(B) It is a kind of application software
(C) It is a kind of general software
(D) Both A and C

Answer: (A) It is a type of system software
Explanation: Many textbooks classify a DBMS as system software because it manages data for other programs. (Some books call it application software.)

Q72. A grammar that produces more than one parse tree for the same sentence is called

(A) Contiguous
(B) Ambiguous
(C) Unambiguous
(D) Regular

Answer: (B) Ambiguous
Explanation: A grammar that gives more than one parse tree for the same string is ambiguous.

Q73. Which traversal technique is used to visit each node of a linked list exactly once?

(A) Preorder traversal
(B) Inorder traversal
(C) Postorder traversal
(D) Linear traversal

Answer: (D) Linear traversal
Explanation: A linked list is traversed linearly from the head node to the end, visiting each node once.

Q74. Which of the following is not a Search Engine available over the Internet ?

(A) Google
(B) Bing
(C) Diksha
(D) Yahoo

Answer: (C) Diksha
Explanation: DIKSHA is a government e-learning platform, not a search engine.

Q75. In a PLA, what components are used to implement the combinational logic functions?

(A) AND gates and OR gates
(B) NAND gates and XOR gates
(C) NOR gates and XNOR gates
(D) NOT gates and multiplexers

Answer: (A) AND gates and OR gates
Explanation: A PLA has a programmable AND array followed by a programmable OR array.

Q76. Which protocol is used for sending emails?

(A) HTTP
(B) FTP
(C) SMTP
(D) SNMP

Answer: (C) SMTP
Explanation: SMTP (Simple Mail Transfer Protocol) sends email.

Q77. …………….are the unorganized facts that can be processed to generate meaningful information.

(A) Information
(B) Data
(C) Blog
(D) contexts

Answer: (B) Data
Explanation: Data are raw, unorganised facts that are processed to give information.

Q78. Which one of the following resource is not necessarily required on a file server?

(A) secondary storage
(B) processor
(C) network
(D) monitor

Answer: (D) monitor
Explanation: A file server needs storage, a processor and a network connection; a monitor is not necessary.

Q79. The letter S in the abbreviation HTTPS in context of Networking protocols, stands for :

(A) Single
(B) Static
(C) Secure
(D) Sensitive

Answer: (C) Secure
Explanation: HTTPS = HyperText Transfer Protocol Secure.

Q80. Which version control system is commonly used for collaborative web development projects?

(A) SVN
(B) Git
(C) Mercurial
(D) CVS

Answer: (B) Git
Explanation: Git (used with GitHub/GitLab) is the most common version control system for collaborative web projects.

Q81. The term “DFD” stands for?

(A) Data file diagram
(B) Data flow document
(C) Data flow diagram
(D) None of the above

Answer: (C) Data flow diagram
Explanation: DFD = Data Flow Diagram.

Q82. Which symbol is used to define the start and end of XML tags?

(A) < >
(B) { }
(C) [ ]
(D) ( )

Answer: (A) < >
Explanation: XML tags are written inside angle brackets, e.g. <name> … </name>.

Q83. What is the full form of FTP ?

(A) File Transfer Protocol
(B) File Transmission Protocol
(C) Fast Transfer Protocol
(D) Fast Transmission Protocol

Answer: (A) File Transfer Protocol
Explanation: FTP = File Transfer Protocol.

Q84. The language accepted by Push down Automaton:

(A) Recursive Language
(B) Context free language
(C) Linearly Bounded language
(D) All of the mentioned

Answer: (B) Context free language
Explanation: A pushdown automaton accepts exactly the context-free languages.

Q85. What is an encryption system that uses two keys: a public key that everyone can have and a private key for only the recipient?

(A) Encryption
(B) IDS
(C) Security Audit software
(D) Public key Encryption

Answer: (D) Public key Encryption
Explanation: Public-key (asymmetric) encryption uses a public key to encrypt and a private key to decrypt.

Q86. Let u=’1101’, v=’0001’, then uv=11010001 and vu= 00011101.Using the given information what is the identity element for the string?

(A) u-1
(B) v-1
(C) u-1v-1
(D) ε

Answer: (D) ε
Explanation: The empty string ε is the identity for concatenation: uε = εu = u.

Q87. Which keyword is used to create an instance of a class in most programming languages?

(A) alloc
(B) new
(C) create
(D) instance

Answer: (B) new
Explanation: Most OOP languages (Java, C++, C#) create objects with the ‘new’ keyword.

Q88. Which of the following is known as a set of entities of the same type that share same properties, or attributes?

(A) Relation set
(B) Tuples
(C) Entity set
(D) Entity Relation model

Answer: (C) Entity set
Explanation: An entity set is a collection of entities of the same type that share the same attributes.

Q89. What is the time complexity of Merge Sort for sorting an array of size “n”?

(A) O(n)
(B) O(log n)
(C) O(n log n)
(D) O(n^2)

Answer: (C) O(n log n)
Explanation: Merge sort always takes O(n log n) time.

Q90. Maximum read range of RFID module is?

(A) 10 CM
(B) 5 CM
(C) 15 CM
(D) 2 CM

Answer: (B) 5 CM
Explanation: Common RFID reader modules such as the RC522 have a maximum read range of about 5 cm.

Q91. Which type of register is primarily used to temporarily hold data during arithmetic and logical operations in a microprocessor?

(A) Shift register
(B) Parallel register
(C) Accumulator register
(D) Counter register

Answer: (C) Accumulator register
Explanation: The accumulator holds an operand and the result of ALU operations.

Q92. Safeguards in an operating system are mechanisms used to:

(A) Ensure the efficient utilization of CPU time
(B) Prevent data loss during power outages
(C) Enhance the performance of I/O operations
(D) Protect against unauthorized access and security breaches

Answer: (D) Protect against unauthorized access and security breaches
Explanation: OS safeguards (authentication, access control) protect against unauthorised access and security breaches.

Q93. Which of the following is a service for real-time text communication on the internet ?

(A) e-Learning
(B) FTP
(C) Video conferencing
(D) Chat

Answer: (D) Chat
Explanation: Chat is a service for real-time text conversation over the internet.

Q94. If the dictionary D1 is defined as D1 = {1: ‘a’, 2: ‘b’}, which of the following statements is incorrect and hence will result in an error?

(A) D1.get(1)
(B) D1.get(3)
(C) D1.del(1)
(D) D1.clear(1)

Answer: (C) D1.del(1)
Explanation: A dictionary has no del() method; an item is removed with del D1[1] or D1.pop(1). (D1.clear(1) would also fail, since clear() takes no argument.)

Q95. Telnet is commonly used for:

(A) Secure file transfers
(B) Remote terminal access
(C) Web browsing
(D) Email communication

Answer: (B) Remote terminal access
Explanation: Telnet provides remote terminal access to another computer (without encryption).

Q96. Separate chaining involves storing collided elements in separate data structures, typically in:

(A) Linked lists
(B) Arrays
(C) Stacks
(D) Queues

Answer: (A) Linked lists
Explanation: In separate chaining, each hash slot points to a linked list of the keys that collide there.

Q97. PDA can be represented with the help of

(A) Instantaneous description
(B) Transition diagram
(C) Transition table
(D) All of these

Answer: (D) All of these
Explanation: A PDA can be shown by instantaneous descriptions, a transition diagram or a transition table.

Q98. Which Karnaugh Map simplification technique involves grouping cells that are not adjacent but share a common variable value?

(A) Pair simplification
(B) Quad simplification
(C) Octet simplification
(D) Group simplification

Answer: (D) Group simplification
Explanation: Cells on opposite edges of a K-map wrap around and can be grouped together even though they do not look adjacent; the options do not name this clearly.

Q99. which of the following is/ are components of Expert Systems?

(A) Knowledge Base
(B) Inference logic
(C) User Interface
(D) All of the above

Answer: (D) All of the above
Explanation: An expert system has a knowledge base, an inference engine and a user interface.

Q100. Arrange the following electromagnetic waves in increasing order of their frequency range. (A) Microwaves (B) Infrared Waves (C) Light Waves (D) Radio Waves Choose the correct answer from the options given below :

(A) (A), (C), (D), (B)
(B) (D), (C), (B), (A)
(C) (B), (A), (D), (C)
(D) (D), (A), (B), (C)

Answer: (D) (D), (A), (B), (C)
Explanation: In increasing frequency: radio waves < microwaves < infrared < visible light, i.e. (D), (A), (B), (C).

Part II: Teaching Aptitude (Q101–130)

Q101. The mirror of the Society is:

(A) playground
(B) community
(C) Hospital
(D) School

Answer: (D) School
Explanation: A school is called the mirror of society because it reflects society’s values and culture.

Q102. The number of domains in taxonomies of educational objective is

(A) Two
(B) Three
(C) Five
(D) Six

Answer: (B) Three
Explanation: Bloom’s taxonomy has three domains: cognitive, affective and psychomotor.

Q103. Who has developed the ‘Guidelines on information literacy for lifelong learning?

(A) RUSA
(B) ACRL
(C) SCONUL
(D) IFLA

Answer: (D) IFLA
Explanation: IFLA published the ‘Guidelines on Information Literacy for Lifelong Learning’ (2006).

Q104. Which type of lesson plan is simple and straightforward?

(A) Daily lesson plan
(B) Weekly lesson plan
(C) Sequential lesson plans
(D) Monthly lesson plan

Answer: (A) Daily lesson plan
Explanation: A daily lesson plan is the simplest and most direct type of plan.

Q105. The most natural and simple way of teaching a lesson is to proceed from Statement I. something that the students already know Statement II. those facts which are unknown to the learners Statement III. Examples Statement IV. Illustrations Choose the correct option:-

(A) I, III and IV
(B) Only I
(C) Only II
(D) III and IV

Answer: (B) Only I
Explanation: Teaching should proceed from the known to the unknown, starting with what students already know.

Q106. Which one of the following options best describes progressive education?

(A) Learning by doing, project method, cooperative learning
(B) Thematic units, regular unit tests, ranking
(C) Personalized learning, ability grouping, labelling students
(D) Project method, ability grouping, ranking

Answer: (A) Learning by doing, project method, cooperative learning
Explanation: Progressive education focuses on learning by doing, projects and cooperative learning, not ranking or labelling.

Q107. In M.C.Q the correct option is:

(A) Response
(B) Answer
(C) Distractors
(D) None of these

Answer: (B) Answer
Explanation: In an MCQ the correct option is the answer (key); the wrong options are distractors.

Q108. Which of the following is a sign of motivated teaching?

(A) Maximum presence of students in the class
(B) Asking questions by students
(C) Pin drop silence in the class
(D) Complition of home assignment

Answer: (B) Asking questions by students
Explanation: Students asking questions shows they are curious and engaged, a sign of motivated teaching.

Q109. In M.C.Qs the statement of the problem is:

(A) Option
(B) Distractor
(C) Premise
(D) Stem

Answer: (D) Stem
Explanation: The question part of an MCQ is called the stem.

Q110. The stage in problem solving that includes the preparation of suitable hypothesis for investigation.

(A) Survey
(B) Planning for action
(C) Problem description
(D) Discussion

Answer: (B) Planning for action
Explanation: Forming a suitable hypothesis to investigate is part of planning for action in problem solving.

Q111. While discussing about friction, a teacher gave a number of examples to explain the concept. Some of the examples where friction is useful in our day-to-day life as-quoted by the teacher are given below. I. We are able to write because of friction between the tip of the pen and the paper. II. We are able to walk because of friction between our feet and the ground. III. A ball thrown vertically upwards comes back to us due to friction. IV. We are able to stop a moving vehicle by applying brakes because of friction. The correct examples were

(A) III, IV and I
(B) IV, I and II
(C) I, III and IV
(D) II, III and IV

Answer: (B) IV, I and II
Explanation: Writing, walking and braking depend on friction; a ball returns down because of gravity, not friction.

Q112. Having variety of question sets in a question paper increases it __________

(A) Objectivity
(B) Reliability
(C) Validity
(D) Difficulty

Answer: (C) Validity
Explanation: Varied questions cover more of the content, which increases the content validity of the paper.

Q113. If you join a teacher fraternity and choose to dress like most of the others in your group, you are exhibiting-

(A) group identity
(B) group obedience
(C) group compliance
(D) group conformity

Answer: (D) group conformity
Explanation: Changing your behaviour (such as dress) to match a group is called conformity.

Q114. What is the steps for constructing a test ?

(A) Planning and preparing the test
(B) Try Out the test
(C) Evaluating the test
(D) All of these

Answer: (D) All of these
Explanation: Building a test involves planning and preparing it, trying it out and evaluating it.

Q115. Continuous and Comprehensive evaluation was initiated by:

(A) NCTE
(B) CBSE
(C) NCERT
(D) SCERT

Answer: (B) CBSE
Explanation: CBSE introduced Continuous and Comprehensive Evaluation (CCE) in its schools in 2009.

Q116. Learning is generally considered as a permanent change in behavior’ based on

(A) Practice and experience.
(B) Practice and challenge.
(C) Challenge and experience.
(D) Challenge and reinforcement.

Answer: (A) Practice and experience.
Explanation: Learning is a relatively permanent change in behaviour that comes from practice and experience.

Q117. The characteristics of discussion method is

(A) Ensure maximum participation
(B) Students have the opportunity to criticize and evaluate.
(C) Logical and meaningful criticism should be accepted
(D) All of them

Answer: (D) All of them
Explanation: The discussion method encourages maximum participation, critical evaluation and acceptance of logical criticism.

Q118. Which of the following teaching method is focused on the development of creative minds?

(A) Project
(B) Brain storming
(C) Observation
(D) Demonstration

Answer: (B) Brain storming
Explanation: Brainstorming encourages free generation of ideas and develops creativity.

Q119. Which type of lesson plan is concise and focused on specific concepts or skills?

(A) Sequential lesson plans
(B) Weekly lesson plan
(C) Daily lesson plan
(D) Monthly lesson plan

Answer: (C) Daily lesson plan
Explanation: A daily lesson plan is short and focused on the specific concepts or skills of one lesson.

Q120. The 5E learning cycle boosts student engagement and motivation through

(A) Constructivist approach
(B) Humanistic approach
(C) Naturalistic approach
(D) Pragmatist approach

Answer: (A) Constructivist approach
Explanation: The 5E cycle (Engage, Explore, Explain, Elaborate, Evaluate) is based on constructivism.

Q121. The part of the curriculum designed to meet the needs of all students is:

(A) General education
(B) Specialized education
(C) The extra-curriculum
(D) The program of studies

Answer: (A) General education
Explanation: General education is the common part of the curriculum meant for all students.

Q122. To demonstrate success by focusing on the learner’s desired outcome, a reasonable list of_____________objectives should be provided.

(A) Informational
(B) Mastery
(C) Challenging
(D) General

Answer: (B) Mastery
Explanation: Mastery objectives state the specific outcomes learners must achieve to show success.

Q123. In comparing lecture and demonstration lessons, which one of the following is not true?

(A) Slow children derive benefit from a lecture than brighter one
(B) There are more activities for the students in a demonstration lesson
(C) The lecture method is more conductive and useful for larger group
(D) It is difficult to ascertain students’ learning in a lecture session

Answer: (A) Slow children derive benefit from a lecture than brighter one
Explanation: Slow learners do not gain more from lectures than bright students, so statement A is not true.

Q124. Which one of the following is the duty of a class teacher?

(A) Check the books, exercise books and bages of the students suddenly
(B) Check the lunch boxes of the students and advise them to take healthy food
(C) Check cleanliness of the class
(D) All of these

Answer: (C) Check cleanliness of the class
Explanation: Keeping the classroom clean is a normal duty of a class teacher; sudden checks of bags and lunch boxes are not.

Q125. The most expected immediate outcome of teaching is-

(A) Changes in the behavior of students in a desirable direction.
(B) Development of the total personality of students.
(C) Building characters of the students.
(D) Getting selected for a suitable job.

Answer: (A) Changes in the behavior of students in a desirable direction.
Explanation: The immediate expected outcome of teaching is a desirable change in students’ behaviour.

Q126. To select subject matter, one should consider student’s:

(A) I.Q
(B) Class
(C) Health
(D) Physical age

Answer: (D) Physical age
Explanation: Subject matter should suit the learner’s age and stage of development.

Q127. Micro teaching was first adopted at Stanford University by

(A) Stephen M Corey
(B) Dwight W Allen
(C) John Dewey
(D) Arthur Cunningham

Answer: (B) Dwight W Allen
Explanation: Micro-teaching was developed at Stanford University in 1963 by Dwight W. Allen and colleagues.

Q128. Introduce a problem that students might not be able to solve yet is an example of

(A) Explore
(B) Engage
(C) Explain
(D) Elaborate

Answer: (B) Engage
Explanation: Posing a problem students cannot solve yet sparks curiosity, which is the Engage stage of the 5E model.

Q129. Full form of SIOP Model is

(A) Sheltered Intervention Observation Protocol
(B) Sheltered Instruction Observation Protocol
(C) Sheltered Instruction Objection Protocol
(D) Sheltered Intervention Objection Protocol

Answer: (B) Sheltered Instruction Observation Protocol
Explanation: SIOP = Sheltered Instruction Observation Protocol.

Q130. Which one of the following is the most suitable to improve children’s learning?

(A) Regular assessment test should be conducted.
(B) Teacher should explain the content using different examples and illustrations.
(C) All types of learning material should be there in the class.
(D) Teacher should facilitate children to interact with each other on real-life situations.

Answer: (D) Teacher should facilitate children to interact with each other on real-life situations.
Explanation: Children learn best by interacting with each other about real-life situations (constructivist approach).

Part III: General Awareness & Reasoning (Q131–150)

Q131. Which one among the following is NOT a major oil field located in Gujarat?

(A) Ankaleshwar
(B) Kosamba
(C) Mehsana
(D) Moran

Answer: (D) Moran
Explanation: Moran is an oil field in Assam; Ankleshwar, Kosamba and Mehsana are in Gujarat.

Q132. Who among the following is the author of the book ‘The Indian Struggle 1920 – 1942’ ?

(A) Vinayak Damodar Savarkar
(B) Subhas Chandra Bose
(C) Vallabhbhai Patel
(D) Sarat Chandra Bose

Answer: (B) Subhas Chandra Bose
Explanation: ‘The Indian Struggle 1920–1942’ was written by Subhas Chandra Bose.

Q133. 7 is to 34 as 5 is to ?

(A) 33
(B) 24
(C) 54
(D) 41

Answer: (B) 24
Explanation: Pattern n × 5 − 1: 7 × 5 − 1 = 34, so 5 × 5 − 1 = 24.

Q134. Chronologically arrange the following political events related to Indian National Movement beginning from the earliest : 1. Formation of Swaraj Party 2. Communal Award 3. Lucknow Pact 4. Simla Conference Select the correct answer from the given options:

(A) 3, 1, 2, 4
(B) 1, 3, 2, 4
(C) 2, 1, 4, 3
(D) 1, 2, 3, 4

Answer: (A) 3, 1, 2, 4
Explanation: Lucknow Pact (1916), Swaraj Party (1923), Communal Award (1932), Simla Conference (1945), so 3, 1, 2, 4.

Q135. As per the Cabinet Resolution of 1st January 2015, the NITI Aayog consists of : 1. Prime Minister of India 2. Governing Council comprising of Chief Minister of all the States and Leiutenant Governors of Union Territories 3. Rural Development Minister 4. Chief Executive Officer to be appointed by the Prime Minister Select the correct answer from the given options :

(A) 1, 2 and 3
(B) 1, 2 and 4
(C) 1 and 2 only
(D) 3 and 4 only

Answer: (B) 1, 2 and 4
Explanation: NITI Aayog has the PM as Chairperson, a Governing Council of all CMs and LGs, and a CEO appointed by the PM.

Q136. Which nutrient protects us from diseases?

(A) Vitamin and minerals
(B) Fats and carbohydrates
(C) Protein
(D) All of these

Answer: (A) Vitamin and minerals
Explanation: Vitamins and minerals are the protective nutrients that build immunity.

Q137. In the given letter series what letter will come in place of the question Symbol. DIL, GLO, JOR, ?

(A) MRV
(B) MRQ
(C) MRU
(D) NRO

Answer: (C) MRU
Explanation: Each letter moves 3 places ahead: D→G→J→M, I→L→O→R, L→O→R→U, giving MRU.

Q138. B is the Aunt of C. A is the Husband of B. B is the sister of D. Tell how A is related to D?

(A) Uncle
(B) Brother-in-Law
(C) Niece
(D) Son

Answer: (B) Brother-in-Law
Explanation: A is B’s husband and B is D’s sister, so A is D’s brother-in-law.

Q139. The joint between separate faces of a solid is called an………………

(A) edge
(B) face
(C) vertex
(D) None of these

Answer: (A) edge
Explanation: The line where two faces of a solid meet is an edge.

Q140. Which is the longest National Highway in India?

(A) NH 5
(B) NH44
(C) NH10
(D) NH 15

Answer: (B) NH44
Explanation: NH 44 (Srinagar to Kanyakumari) is the longest national highway in India.

Q141. Aaron weight 49 kg 357 g and Ron weights 32 kg 458 g. Who weighs less and by how much?

(A) Ron weighs less by 16 kg 899 g
(B) Aaron weighs less by 16 kg 899 g
(C) Ron weighs more by 16 kg 899 g
(D) Aaron weighs more by 16 kg 899 g

Answer: (A) Ron weighs less by 16 kg 899 g
Explanation: 49.357 kg − 32.458 kg = 16.899 kg, so Ron weighs less by 16 kg 899 g.

Q142. If we combine two consecutive triangular numbers, we get?

(A) Rational Number
(B) Whole Number
(C) Perfect Square
(D) Prime Number

Answer: (C) Perfect Square
Explanation: The sum of two consecutive triangular numbers is a perfect square, e.g. 3 + 6 = 9.

Q143. Which of the following is a waterborne disease?

(A) Measles
(B) malaria
(C) Lung disease
(D) Hepatitis

Answer: (D) Hepatitis
Explanation: Hepatitis A and E spread through contaminated water.

Q144. “Family is a unit consisting of a mother, father and their two children”. This statement is

(A) incorrect, because the statement should specify that the children are biological
(B) incorrect, because there are many kinds of families and one cannot classify family as being of only one kind
(C) correct, since this is an ideal family size
(D) correct, because this is what all Indian families are like

Answer: (B) incorrect, because there are many kinds of families and one cannot classify family as being of only one kind
Explanation: There are many types of families (joint, single-parent, etc.), so one fixed definition is incorrect.

Q145. If the median of the data 30,8,7,3,17,15,21,24,29,23 is x and the median of the data obtained by replacing 3 by 33 and 8 by 18 in the above data is y, then what is the difference between y and x ?

(A) 2
(B) 3
(C) 4
(D) 1

Answer: (B) 3
Explanation: Original sorted median = (17 + 21)/2 = 19; new data median = (21 + 23)/2 = 22; difference = 3.

Q146. Choose the correct option instead of the question mark in the given question. 456 : 15 :: 627 : ?

(A) 12
(B) 15
(C) 18
(D) 21

Answer: (B) 15
Explanation: The sum of the digits: 4 + 5 + 6 = 15, so 6 + 2 + 7 = 15.

Q147. In English alphabet which Letter is in between the Letter s and the Letter G ?

(A) N
(B) M
(C) L
(D) P

Answer: (B) M
Explanation: G is the 7th letter and S the 19th; the middle one is the 13th letter, M.

Q148. Which of the following are macronutrients commonly found in soil?

(A) Carbon, Hydrogen, Oxygen
(B) Nitrogen, Phosphorus, Potassium
(C) Iron, Manganese, Zinc
(D) Boron, Copper, Molybdenum

Answer: (B) Nitrogen, Phosphorus, Potassium
Explanation: N, P and K are the primary macronutrients that plants take from soil.

Q149. ABCD is a rhombus in which ∠ADB = 25 Degree. Then, the value of ( 2∠BAD – ∠ABC ) is :

(A) 230 Degree
(B) 240 Degree
(C) 210 Degree
(D) 260 Degree

Answer: (C) 210 Degree
Explanation: The diagonals bisect the angles: ∠ADC = 50°, so ∠BAD = 130° and ∠ABC = 50°. 2 × 130 − 50 = 210°.

Q150. Globalization signifies which of the following :

(A) Time-space compression
(B) The integration of the world economy
(C) The growth of supra- territorial relations between people
(D) All the above

Answer: (D) All the above
Explanation: Globalization means time-space compression, economic integration and the growth of supra-territorial relations.

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