Category: M.Sc.CSIT

• A primary key uniquely identifies a tuple (row) in a relation (table), and there can only be one primary key for each table.
• A table can have multiple foreign keys, super keys, and candidate keys, but the primary key is unique.

Hence, the correct answer is option a. A relation can have only one
primary key

The actual execution order in SQL is:

1. 1. FROM: Determines the source of data.
   2. WHERE: Filters the data based on the given condition.
   3. SELECT: Projects the desired columns or computed values from the filtered data.

Hence, the correct answer is option d. FROM, WHERE, SELECT

4NF (Fourth Normal Form) deals with multi-valued dependencies and ensures that there are no non-trivial multi-valued dependencies in a table unless they are a candidate key.

Hence, the correct answer is option c. 4NF

After a transaction is completed successfully, it moves to the committed state, which means the changes made by the transaction are now permanent in the database.

Hence, the correct answer is option b. Committed

• The Waterfall model is best suited for projects where the requirements are clear, precise, and unlikely to change.
• This model follows a linear sequential approach, meaning each phase (e.g., requirements gathering, design, implementation) must be completed before the next begins.
• It is not suitable for projects with evolving requirements or uncertain user needs, where iterative approaches like Prototyping, Spiral, or Agile are preferred

Hence, the correct answer is option a. Waterfall

Data Flow Diagrams (DFDs) are used in structured development methodologies to model processes and the flow of data between them.

They represent how data moves through a system, showing inputs, processes, and outputs.

Other diagrams like:

Use-case diagrams focus on system interactions with actors.

Entity-Relationship diagrams (ERDs) model data relationships.

Class diagrams are used in object-oriented design.

Hence, the correct answer is option c. Data flow diagram

A pilot installation involves implementing a system in a single location or a small part of the organization before rolling it out completely.

This approach helps in testing the system and identifying any issues in a controlled environment.

Other types of installations:

Direct installation: Immediate replacement of the old system.

Parallel installation: Running the old and new systems together for a period.

Phased installation: Gradual implementation across the organization.

Hence, the correct answer is option d. Pilot installation

Hashed file organization uses a hashing algorithm to determine the address or location of a record in storage.

It provides efficient direct access to data and is commonly used for fast lookups.

Other file organizations:

Sequential file organization: Records are stored in a sequential order, usually sorted by a key.

Indexed file organization: Uses an index to map keys to storage locations.

Hence, the correct answer is option c. Hashed file organization

ARPANET (Advanced Research Projects Agency Network) was the first network to implement the TCP/IP protocol suite. It laid the foundation for the modern internet.

It was developed in the late 1960s by the U.S. Department of Defense.

Other options:

CSNET: A computer science network for universities and research institutions.

ASAPNET and CNNET are not relevant networks in this context.

Hence, the correct answer is option b. ARPANET

The Internet layer in the TCP/IP model is responsible for routing data across different networks. It ensures the packets reach their destination by selecting the best path through interconnected networks.

Key functions of the Internet layer include addressing (IP addresses) and routing. The most notable protocol at this layer is the Internet Protocol (IP).

Other layers:

Network Access Layer: Handles hardware addressing and data transmission over physical links.

Transport Layer: Ensures reliable data delivery (e.g., using TCP or UDP).

Physical Layer: Focuses on the physical transmission of raw bits over a communication medium.

Hence, the correct answer is option b. Internet layer

A Class C address has a default subnet mask of 255.255.255.0 (which allows 1 network with 256 IPs).

To divide it into 8 subnets, we need 3 extra bits for subnetting (since 2^3=8).

Adding these 3 bits to the default subnet mask results in: 255.255.255.224(binary: 11111111.11111111.11111111.11100000)

This provides:

8 subnets, each with 2^5 = 32 IP addresses.

Usable IPs per subnet: 32−2=30 (subtracting 1 for the network address and 1 for the broadcast address).

Hence, the correct answer is option c. 255.255.255.224

The UDP (User Datagram Protocol) header is fixed at 8 bytes.

It includes the following fields, each 2 bytes long (4 fields × 2 bytes = 8 bytes):

Source Port (2 bytes)

Destination Port (2 bytes)

Length (2 bytes)

Checksum (2 bytes)

UDP is a connectionless protocol with minimal overhead, making it faster but less reliable compared to TCP.

Hence, the correct answer is option a. 8 bytes

Frames were introduced in HTML 4.0 to divide a browser window into multiple sections, each capable of displaying a different document.

Other options such as Canvas, SVG, Video, and Geolocation were introduced or became widely supported with HTML5.

Frames are now deprecated in HTML5 due to usability and accessibility concerns.

Hence, the correct answer is option d. Frames

The Document Object Model (DOM) is a programming interface for web documents. It represents the structure of an HTML or XML document as a tree of objects that can be manipulated using programming languages like JavaScript.

Example: The DOM allows developers to dynamically change the content, structure, or styling of a webpage

Hence, the correct answer is option b. Document object model

In CSS, the class selector is represented by a dot (.) followed by the class name.

Hence, the correct answer is option d. dot (.)

• Off-site optimization refers to activities performed outside a website to improve its search engine ranking, with backlinks being a major factor.
• Backlinks (incoming links) from other websites indicate a site’s authority and popularity, which helps improve search rankings.
• Other types of optimizations:
  • Technical optimization: Focuses on the structure and performance of the website (e.g., page speed, mobile-friendliness).
  • On-site optimization: Involves improving on-page content and keyword usage.

Hence, the correct answer is option c. off-site

Option b is the transitive rule

Hence, the correct answer is option b

The inclusion and exclusion principle is |A1 u A2 | = |A1| + |A2| – |A1 n A2|

Hence, the correct answer is option d. |A1 u A2 | = |A1| + |A2| – |A1 n A2|

A complete graph Kn​ is a graph where every pair of vertices is connected by an edge.

To properly colour a graph, adjacent vertices must have different colours.

In Kn​, each vertex is adjacent to every other vertex. Hence, each vertex requires a unique colour.

Therefore, the number of colours required to colour Kn​ is equal to the number of vertices, $n$.

Hence, the correct answer is option b. n

• This is based on the Max-Flow Min-Cut Theorem in network flow theory.
• The theorem states that the maximum value of the flow in a flow network is equal to the minimum capacity that, when removed, disconnects the source from the sink.
• In practical terms:
  • The maximal flow cannot exceed the minimal cut because the cut represents the bottleneck in the network.
• Hence, the value of maximal flow is always less than or equal to the value of minimal cut.

Hence, the correct answer is option d. Value of maximal flow is always less than or equal to the value of minimal cut

• A digital signature is a cryptographic method used to verify the authenticity and integrity of digital data.
• It involves encrypting a hash (unique summary) of the data with the sender’s private key, which can be verified by the receiver using the sender’s public key.
• The other options are incorrect because:
  • Scanned signature and handwritten signature are physical, not digital.
  • Signature in binary form does not accurately describe a digital signature.

Hence, the correct answer is option c. encrypting information

• The Program Counter (PC) points to the address of the next instruction to be executed.
• The instruction at the memory address specified by the PC is fetched and loaded into the Instruction Register (IR) for decoding and execution.
• Other options:
  • Program Counter (PC): Holds the memory address of the next instruction.
  • Memory Address Register (MAR): Holds the address of the memory location to be accessed.
  • Memory Data Register (MDR): Temporarily stores data being transferred to/from memory.

Hence, the correct answer is option d. Instruction register

Steps to convert A20(hexadecimal) to octal:

1. Convert A20​ to binary: A=1010, 2=0010, 0=0000  ⟹  A2016=1010 0010 0000 ​
2. Group binary digits into sets of 3 (from right): 101 000 100 000=1040

• Therefore, A20=1040​.

Hence, the correct answer is option a. 1040

Borders in MS Word can be applied to:

• Cells (in tables).
• Paragraphs (around blocks of text).
• Text (individual words or lines).

Hence, the correct answer is option d. All of above

• The pre-processor processes directives (commands that begin with #), such as #include and #define, before actual compilation starts.
• #include <stdio.h> is a pre-processor directive that includes the standard input/output library for the program.
• Other options:
  • void main(int argc, char **argv): Part of the main function, executed during runtime, not pre-processing.
  • return (0): Runtime statement.
  • None of the above is incorrect because #include is executed by the pre-processor.

Hence, the correct answer is option b. #include <stdio.h>

Output of the following code is 15

Hence, the correct answer is option b. 15

The printf(“Hello World!”); will not execute at all, because the loop condition is false right from the start.

Hence, the correct answer is option b. 0 times

In C, the two valid ways to comment out code are:

1. Single-line comment: Use // to comment out a single line.
   • Example: // printf(“%d”, i);
2. Multi-line comment: Use /* */ to comment out one or more lines.
   • Example: /* printf(“%d”, i); */

Hence, the correct answer is option b. // printf(“%d”,i);

• A Deterministic Finite Automaton (DFA) cannot recognize palindromes because it has limited memory and cannot “remember” the second half of the string as it reads it.
• Palindromes require comparing characters from both ends of the string, which a DFA cannot do, as it can only move through a fixed number of states.
• To recognize palindromes, a Pushdown Automaton (PDA) is required, which has additional memory in the form of a stack.

Hence, the correct answer is option b. No

• In regular expressions, A.A* can be simplified to A^+.
• Here’s why:
  • A.A* means “A followed by zero or more occurrences of A”, which is equivalent to A^+ (one or more occurrences of A).

Hence, the correct answer is option a. A^+

A Context-Free Grammar (CFG) is considered ambiguous if there is more than one parse tree or derivation for the same string.

• In an ambiguous grammar, a single string can be generated in multiple ways, leading to different parse trees or derivations. This is problematic because it creates ambiguity in interpreting the structure of the string.
• Option a is related but incomplete because ambiguity is typically identified by the number of parse trees, not just leftmost derivations.
• Option c (“a and b both”) is the most accurate answer but “more than one parse tree” is the primary criterion for ambiguity.

Hence, the correct answer is option b. It has more than one parse tree for a string produced by the grammar

A Universal Turing Machine (UTM) is a Turing machine that can simulate any other Turing machine. It takes a description of another Turing machine and its input, and simulates the computation that the described machine would carry out. The UTM is a fundamental concept in the theory of computation because it shows that a single machine can perform any computation that is computable.

• Option a (“Nested Turing machine”) is incorrect; this term doesn’t refer to a known concept in computation theory.
• Option c (“Multitape Turing machine”) refers to a Turing machine with multiple tapes, which is more powerful than a standard Turing machine but is not necessarily a universal machine.
• Option d (“Turing machine with state as storage”) refers to a machine model with different architecture but does not specifically describe a Universal Turing Machine.

Hence, the correct answer is option b. Universal turing machine

• The Fibonacci series is a mathematical sequence, but it is not a method for generating random numbers.
• Random numbers are typically generated through methods such as:
  • Table of random numbers: Pre-generated lists of random numbers.
  • Spinning a roulette wheel: A physical, random process.
  • Computer-generated random numbers: Using algorithms to generate pseudo-random numbers in a computer.

Hence, the correct answer is option d. Fibonacci series

• A dynamic model is used to simulate systems that change over time based on various activities, inputs, and interactions.
• Static models do not account for changes over time; they represent a snapshot of the system at a particular point in time.
• Analytical and Numerical models can also be used for certain types of analysis, but they do not inherently focus on time-based changes

Hence, the correct answer is option b. Dynamic

• The Monte Carlo Simulation method gets its name from the Monte Carlo Casino in Monaco, which is famous for games of chance involving random outcomes.
• The method relies on the use of random numbers to simulate and solve problems that may be deterministic in principle but are too complex for analytical solutions. It uses statistical sampling techniques to model systems and processes.

Hence, the correct answer is option b. Idea of random number assignment

All the methods listed are commonly used in analyzing simulation results:

• Analysis of variance (ANOVA) is used to analyze the differences between groups and is helpful in simulation analysis when comparing multiple sets of results.
• T-test compares the means of two groups to determine if there is a significant difference.
• Regression analysis is used to determine relationships between variables, which can be applied to simulation results to predict outcomes.

Hence, the correct answer is option d. All of the above

• An LR parser (Left-to-right, Rightmost derivation) is a bottom-up parser. It builds the parse tree starting from the leaves (tokens) and works its way up to the root (start symbol).
• It processes the input from left to right and produces a rightmost derivation in reverse. LR parsers are used in many compilers.

Hence, the correct answer is option a. bottom up parser

• Three-address code (TAC) is an intermediate code representation used in compilers, and it involves at most three addresses or operands in each instruction.
• Typically, it consists of a left-hand operand, a right-hand operand, and a result address.
• Example: t1 = a + b

Hence, the correct answer is option a. At most three addresses

The First(S) is {b,c}

Hence, the correct answer is option c.{b,c}

• A decorated parse tree is an output from the semantic analyser phase of a compiler. In this phase, additional information is added to the parse tree (such as type information, symbol table entries, etc.) to ensure that the program follows semantic rules.
• The lexical analyser produces tokens, and the syntax analyser generates the parse tree, but the semantic analyser decorates the tree with additional information needed for further processing.

Hence, the correct answer is option c. Semantic analyser

An AVL tree (named after its inventors Adelson-Velsky and Landis) is a self-balancing binary search tree in which the height difference (balance factor) between the left and right sub-trees of any node is at most 1. This ensures that the tree remains balanced, providing efficient search operations.

Hence, the correct answer is option a. AVL tree

• The postfix (Reverse Polish) notation is obtained by following these steps:
  1. (A + B) becomes AB+
  2. (C * D – E) becomes CD*E-
  3. The whole expression (A + B) * (C * D – E) becomes AB+ CD*E- *
  4. Multiply by F gives AB+ CD*E- *F*
  5. Finally, divide by G results in AB+ CD*E- *F*G/

Hence, the correct answer is option d. AB+ CD*E- *F*G/

The base condition in recursion is essential to stop the recursion from continuing indefinitely. Without it, the function will keep calling itself and consuming memory. This will eventually cause a stack overflow, as the stack space allocated for function calls is exhausted

Hence, the correct answer is option b. Stack Overflow

After the first partitioning in quicksort, the pivot element is placed in its correct sorted position. All elements to the left are smaller, and all elements to the right are larger.
In the given array, the pivot could be 7 or 9, depending on the implementation of the partitioning logic. The partitioning ensures that all elements on the left of the pivot are smaller and all elements on the right are larger.

Hence, the correct answer is option a. The pivot could be either the 7 or the 9

Euler’s method is a simple numerical method for solving ordinary differential equations (ODEs) by approximating the solution using the tangent (first derivative) at each point in the interval.

It uses the slope (or derivative) at a current point to estimate the value of the function at the next point in the solution.

Hence, the correct answer is option b. Euler’s method

• Truncation error arises from approximating a mathematical procedure, such as using a finite number of terms in a series expansion.
• Round-off error occurs due to the finite precision of arithmetic in computers.
• In general, truncation error is more significant than round-off error, and the ratio is typically considered 2:1 for estimation purposes.

Hence, the correct answer is option a. 2:1

• The Newton-Raphson method for finding roots of equations is highly sensitive to the initial guess (starting value).
• A poor choice of the starting value may lead to divergence or convergence to an incorrect root.
• Methods like False Position and Gauss-Seidel are less sensitive in comparison.

Hence, the correct answer is option a. Newton-Raphson method

A partial differential equation (PDE) involves partial derivatives of a function with respect to two or more independent variables.

Hence, the correct answer is option c. Two or more independent variables

• In Image Space Methods, visibility is determined pixel by pixel on the projection plane. The algorithm checks each pixel to see which object is visible at that location.
• Object Space Methods work by comparing objects in the 3D space to determine visibility relationships.
• Image Space Methods are more commonly used in computer graphics due to their direct pixel-level approach.

Hence, the correct answer is option b. Image Space Method

• A reflection about the x-axis transforms a point (x,y) to (x,−y).
• A counter-clockwise rotation of 90° transforms (x,y) to (−y,x).
• Combining these transformations gives (−y,−x), which is equivalent to reflection about the line $X$.

Hence, the correct answer is option b. Y = -X

• Bresenham’s circle algorithm is designed to exploit the symmetry of circles. Instead of calculating all points of the circle, it computes points in one octant and uses reflections to generate points in the other seven octants.
• This reduces computation and makes the algorithm efficient.

Hence, the correct answer is option c. One octant first and other by successive reflection

• Bresenham’s line algorithm is an efficient method for rasterizing lines because it uses only integer arithmetic (avoiding floating-point operations).
• Algorithms like the DDA (Digital Differential Analyzer) require floating-point calculations, making them slower in comparison.

Hence, the correct answer is option a. Bresenham’s line algorithm

• A NOT gate inverts its input, meaning it produces the logical complement of the input.
• For example, if the input is 1 (True), the output is 0 (False), and vice versa.

Hence, the correct answer is option a. inverting

A logic gate is a basic building block of digital circuits. It has one or more inputs and a single output, performing basic logical operations like AND, OR, NOT, etc.

Hence, the correct answer is option b. logic gate

• A NOR gate is the combination of an OR gate followed by a NOT gate.
• Its output is High (1) only if all inputs are Low (0).

Hence, the correct answer is option c. High if all of its inputs are low

• A Carry-save adder (CSA) is used to add three or more numbers simultaneously. It saves the carry values to be added in a subsequent step, making it faster for multiple additions.
• Other adders like parallel adders or carry-look-ahead adders are typically designed for adding two numbers.

Hence, the correct answer is option c. Carry-save-adder

• INTR (Interrupt Request) is a hardware interrupt in microprocessors like the 8085. It is triggered by external devices to request the processor’s attention.
• Software interrupts, by contrast, are triggered by program instructions like RST in 8085

Hence, the correct answer is option b. hardware Interrupt

• The POP instruction in 8085 retrieves data from the stack into a specified register pair. However, 30H is not a valid register pair or an acceptable operand for the POP instruction.
• Valid operands include register pairs like B, D, H, and PSW.

Hence, the correct answer is option a. POP 30 H

• The address bus is used by the microprocessor to specify memory locations or I/O ports for communication. It is unidirectional because it only sends addresses from the processor to memory or I/O devices.
• The data bus, in contrast, is bidirectional as it transfers data both to and from the processor.

Hence, the correct answer is option c. address bus of microprocessor is unidirectional

• The 8085 microprocessor supports 246 instructions, which include arithmetic, logical, control, branching, and data transfer operations.
• These instructions are classified into different groups based on functionality.

Hence, the correct answer is option d. 246

Pipelining in computer architecture is similar to an assembly line process in manufacturing, where different stages of execution work simultaneously on different instructions to improve throughput.

Hence, the correct answer is option b. assembly line operation

In the Immediate addressing mode, the operand (value) is explicitly specified in the instruction itself. For example, in MOV A, #10H, the value 10H is directly used.

Hence, the correct answer is option a. Immediate

Shift registers are used to convert data from parallel to serial format or vice versa, enabling data communication between devices operating in different modes.

Hence, the correct answer is option c. shift registers

In floating-point representation, the mantissa is the part of a number that contains the digits (significant digits) after the sign. It represents the precision of the number.

Hence, the correct answer is option d. mantissa

Insertion sort is efficient for small or almost-sorted datasets because it works by incrementally inserting elements into their correct positions.

Hence, the correct answer is option c. insertion sort

A heap is a complete binary tree that satisfies the heap property (either max-heap or min-heap), where the parent node is greater or smaller than its children.

Hence, the correct answer is option b. complete binary tree

The Boolean satisfiability problem (SAT) is the first problem proven to be NP-complete. It means that it is as hard as any problem in NP, and if SAT is solved in polynomial time, all NP problems can also be solved in polynomial time.

Hence, the correct answer is option c. NP complete

Dynamic programming is a technique used to solve optimization problems by breaking them into overlapping subproblems and solving each subproblem only once.

Hence, the correct answer is option b. optimization

A copy constructor is a special constructor in object-oriented programming used to create a new object as a copy of an existing object. This can be used when an object is passed to a function.

Hence, the correct answer is option b. Copy an object so that it can be passed to a function

A class is a logical abstraction because it defines the blueprint for objects, encapsulating data and behaviors logically but not directly implementing them in real-world terms.

Hence, the correct answer is option b. Logical

Class A has the highest level of abstraction because it is farthest from the base class (C) and likely builds upon or abstracts further functionality.

Hence, the correct answer is option a. Class A

Multiple exceptions can be handled using a single catch block by separating exception types with a pipe (|) in languages like Java. However, it’s optional, not mandatory.

Hence, the correct answer is option b. Can be combined into a single catch block

If the time quantum is very large, each process will finish execution before the next process starts, making the scheduling equivalent to First-Come, First-Served (FCFS)

Hence, the correct answer is option d. When time quanta is large for all process.

Total memory = 1 GB = 1024×1024 KB = $1048576$ KB
OS memory = $16$ MB = $16384$ KB
Memory for user = $1032192$ KB
Page size = $8$ KB
Page frames = $=131072$.

Hence, the correct answer is option c. 131072

Thrashing occurs when the system spends more time swapping pages in and out of memory than executing processes. Reducing the number of active processes (degree of multiprogramming) helps solve this issue.

Hence, the correct answer is option c. Decreasing the degree of multiprogramming

Shared memory is the fastest IPC mechanism because processes can directly access the memory area without kernel intervention.

Hence, the correct answer is option a. Shared memory

An admissible heuristic ensures that $)$, where h^*(n) is the true cost to the goal, making it optimistic and guaranteeing optimality in algorithms like A*.

Hence, the correct answer is option c. H(n) never overestimate the cost to reach the goal

The Naïve Bayes model assumes that features (e.g., words) are independent, which simplifies probability calculations despite being an unrealistic assumption.

Hence, the correct answer is option b. Words in the documents are independent from their neighboring words.

“Brother()” represents a function in logic, mapping an individual (Jane) to another individual (her brother).

Hence, the correct answer is option a. Function

Morphological analysis focuses on processing individual words, including breaking them into morphemes (e.g., root words, prefixes, and suffixes).

Hence, the correct answer is option a. Word level processing