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401. A file is sometimes called a:

1. Collection of input data

2. Temporary place to store data

3. Data set

4. Program

Show me the answer

Answer: 3. Data set

Explanation:

• File: A file is a collection of related data stored as a single unit. It is also referred to as a data set in some contexts.

• Conclusion: A file is sometimes called a data set.

402. In MS-DOS, relocatable object files and load modules have extensions:

1. OBJ and .COM or .EXE respectively

2. COM and .OBJ, respectively

3. EXE and .OBJ, respectively

4. DAS and .EXE, respectively

Show me the answer

Answer: 1. OBJ and .COM or .EXE respectively

Explanation:

• MS-DOS File Extensions: In MS-DOS, relocatable object files have the .OBJ extension, and load modules have the .COM or .EXE extension.

• Conclusion: The correct extensions are .OBJ and .COM/.EXE.

403. Resolution of externally defined symbols is performed by:

1. Linker

2. Compiler

3. Loader

4. Assembler

Show me the answer

Answer: 1. Linker

Explanation:

• Externally Defined Symbols: The linker resolves references to externally defined symbols by combining object modules and resolving external references.

• Conclusion: The linker resolves externally defined symbols.

404. In which of the following page replacement policies does Belady’s anomaly occur?

1. FIFO

2. LFU

3. LRU

4. NRU

Show me the answer

Answer: 1. FIFO

Explanation:

• Belady’s Anomaly: Belady’s anomaly occurs in the FIFO page replacement algorithm, where increasing the number of page frames can lead to an increase in the number of page faults.

• Conclusion: FIFO suffers from Belady’s anomaly.

405. Four necessary conditions for deadlock to exist are: mutual exclusion, no-preemption, circular wait, and:

1. Hold and wait

2. Race around condition

3. Deadlock avoidance

4. Buffer overflow

Show me the answer

Answer: 1. Hold and wait

Explanation:

• Deadlock Conditions: The four necessary conditions for deadlock are mutual exclusion, no-preemption, circular wait, and hold and wait.

• Conclusion: Hold and wait is the fourth condition for deadlock.

406. A system program that sets up an executable program in main memory ready for execution is:

1. Assembler

2. Loader

3. Linker

4. Compiler

Show me the answer

Answer: 2. Loader

Explanation:

• Loader: The loader is responsible for loading an executable program into memory and preparing it for execution.

• Conclusion: The loader sets up the program in memory.

407. The principle of locality of reference justifies the use of:

1. Re-entrant code

2. Virtual memory

3. Non-reusable code

4. Cache memory

Show me the answer

Answer: 4. Cache memory

Explanation:

• Locality of Reference: The principle of locality of reference states that programs tend to access the same set of memory locations repeatedly. This justifies the use of cache memory to store frequently accessed data.

• Conclusion: Locality of reference supports the use of cache memory.

408. The details of all external symbols and relocation information (relocation list or map) are provided to the linker by:

1. Macro processor

2. Loader

3. Translator

4. Editor

Show me the answer

Answer: 3. Translator

Explanation:

• Translator: The translator (compiler or assembler) generates the relocation list and external symbol table, which are used by the linker to resolve references.

• Conclusion: The translator provides relocation information to the linker.

409. Scheduling is:

1. Allowing jobs to use the processor

2. Unrelated to performance considerations

3. Not required in uniprocessor systems

4. The same regardless of the purpose of the system

Show me the answer

Answer: 1. Allowing jobs to use the processor

Explanation:

• Scheduling: Scheduling is the process of allocating the CPU to jobs or processes. It ensures that all jobs get a fair share of the processor.

• Conclusion: Scheduling allows jobs to use the processor.

410. Real-time systems are:

1. Primarily used on mainframe computers

2. Used for monitoring events as they occur

3. Used for program analysis

4. Used for real-time interactive users

Show me the answer

Answer: 2. Used for monitoring events as they occur

Explanation:

• Real-Time Systems: Real-time systems are designed to respond to events as they occur, often within strict time constraints.

• Conclusion: Real-time systems monitor events in real-time.

411. Access time is the highest in the case of:

1. Floppy disk

2. Swapping devices

3. Cache

4. Magnetic disk

412. The most common systems security method is:

1. Passwords

2. Firewall

3. Encryption

4. All of the above

Show me the answer

Answer: 1. Passwords

Explanation:

• Passwords: Passwords are the most common and basic method of securing systems. They are used to authenticate users and restrict access to authorized individuals.

• Conclusion: Passwords are the most widely used security method.

413. Poor response times are caused by:

1. Processor busy

2. High paging rates

3. High I/O rate

4. Any of the above

Show me the answer

Answer: 4. Any of the above

Explanation:

• Poor Response Times: Poor response times can be caused by a busy processor, high paging rates (thrashing), or high I/O rates, all of which can lead to delays in processing user requests.

• Conclusion: Any of the listed factors can cause poor response times.

414. Which of the following is a block device?

1. Mouse

2. Terminals

3. Printer

4. Disk

Show me the answer

Answer: 4. Disk

Explanation:

• Block Device: A block device is a storage device that reads and writes data in fixed-size blocks. Disks are examples of block devices.

• Conclusion: Disks are block devices.

415. Which of the following statements is false?

1. The technique of storage compaction involves moving all occupied areas of storage to one end or other of main storage

2. Compaction does not involve relocation of programs

3. Compaction is also known as garbage collection

4. The system must stop everything while it performs compaction

Show me the answer

Answer: 2. Compaction does not involve relocation of programs

Explanation:

• Compaction: Compaction involves relocating programs to consolidate free memory into a single block. It is a form of memory management used to reduce fragmentation.

• Conclusion: Compaction involves relocation of programs.

416. Thrashing can be avoided if:

1. The pages belonging to the working set of the programs are in main memory

2. The speed of the CPU is increased

3. The speed of the I/O processor is increased

4. All of the above

Show me the answer

Answer: 1. The pages belonging to the working set of the programs are in main memory

Explanation:

• Thrashing: Thrashing occurs when the system spends more time swapping pages in and out of memory than executing processes. Keeping the working set of pages in main memory reduces thrashing.

• Conclusion: Thrashing can be avoided by ensuring the working set is in main memory.

417. Operating system:

1. Links a program with the subroutines it references

2. Provides a layered, user-friendly interface

3. Enables the programmer to draw a flowchart

4. All of the above

Show me the answer

Answer: 2. Provides a layered, user-friendly interface

Explanation:

• Operating System Functions: The operating system provides a user-friendly interface and manages resources, but it does not directly link subroutines or enable flowchart drawing.

• Conclusion: The primary role of the OS is to provide a user-friendly interface.

418. A task in a blocked state:

1. Is executable

2. Is running

3. Must still be placed in the run queues

4. Is waiting for something temporarily unavailable

Show me the answer

Answer: 4. Is waiting for something temporarily unavailable

Explanation:

• Blocked State: A task in the blocked state is waiting for an event (e.g., I/O completion) or resource to become available.

• Conclusion: A blocked task is waiting for something temporarily unavailable.

419. Backups should be done:

1. Daily for most installations

2. Weekly for most installations

3. As several image copies, followed by an incremental

4. As several incremental, followed by an image copy

Show me the answer

Answer: 4. As several incremental, followed by an image copy

Explanation:

• Backup Strategy: A common backup strategy is to perform incremental backups regularly and a full image copy periodically. This balances storage requirements and recovery efficiency.

• Conclusion: Incremental backups followed by an image copy is a recommended strategy.

420. Which of the following statements is true?

1. The LRU algorithm pages out pages that have been used recently

2. Thrashing is a natural consequence of virtual memory systems

3. Seek analysis is used for analyzing control-unit busy problems

4. All of the above

Show me the answer

Answer: 2. Thrashing is a natural consequence of virtual memory systems

Explanation:

• Thrashing: Thrashing occurs when the system spends more time swapping pages than executing processes. It is a potential issue in virtual memory systems.

• Conclusion: Thrashing is a natural consequence of virtual memory systems.

421. A flowchart that uses predefined symbols to describe data flow in a system is known as:

1. Program flowchart

2. Data flow diagram

3. System flowchart

4. All of the above

Show me the answer

Answer: 2. Data flow diagram

Explanation:

• Data Flow Diagram: A data flow diagram (DFD) uses predefined symbols to represent the flow of data in a system.

• Conclusion: A DFD describes data flow in a system.

422. Which of the following is true about pseudo code?

1. A machine language

2. A high-level language

3. An assembly language

4. None of the above

Show me the answer

Answer: 4. None of the above

Explanation:

• Pseudo Code: Pseudo code is an informal way of describing algorithms using a mix of natural language and programming constructs. It is not a formal language.

• Conclusion: Pseudo code is not a machine, high-level, or assembly language.

423. A program that converts a high-level language program to a set of instructions that can run on a computer is called a:

1. Compiler

2. Editor

3. Debugger

4. All of the above

Show me the answer

Answer: 1. Compiler

Explanation:

• Compiler: A compiler translates high-level language code into machine code that can be executed by a computer.

• Conclusion: A compiler performs this translation.

424. Which of the following statements is not true about the FORTRAN language?

1. FORTRAN is a high-level language

2. A FORTRAN program, written for the IBM-PC, is totally different from a FORTRAN program written for execution on the SUN machine

3. FORTRAN is extensively used to write programs for performing scientific computations

4. All of the above

Show me the answer

Answer: 2. A FORTRAN program, written for the IBM-PC, is totally different from a FORTRAN program written for execution on the SUN machine

Explanation:

• FORTRAN Portability: FORTRAN programs are generally portable across different platforms, with minor modifications for system-specific features.

• Conclusion: FORTRAN programs are not "totally different" across platforms.

425. The initial value of the semaphore that allows only one of the many processes to enter their critical section is:

1. 8

2. 1

3. 16

4. 0

Show me the answer

Answer: 2. 1

Explanation:

• Semaphore Initialization: A semaphore initialized to 1 allows only one process to enter the critical section at a time, enforcing mutual exclusion.

• Conclusion: The initial value of the semaphore is 1.

426. The principles of structured programming forbid the use of:

1. WHILE-DO

2. IF-THEN-ELSE

3. GO TO

4. DO-WHILE

Show me the answer

Answer: 3. GO TO

Explanation:

• Structured Programming: Structured programming discourages the use of GO TO statements, as they can lead to unstructured and hard-to-maintain code.

• Conclusion: GO TO is forbidden in structured programming.

427. Which of the following is necessary to work on a computer?

1. Compiler

2. Assembly

3. Operating system

4. Interpreter

Show me the answer

Answer: 3. Operating system

Explanation:

• Operating System: The operating system is essential for managing hardware resources and providing a platform for running applications.

• Conclusion: An operating system is necessary to work on a computer.

428. Dividing a project into segments and smaller units in order to simplify the analysis, design, and programming efforts is known as:

1. Modular approach

2. Bottom-up approach

3. Top-down approach

4. Left-right approach

Show me the answer

Answer: 1. Modular approach

Explanation:

• Modular Approach: Dividing a project into smaller, manageable modules simplifies analysis, design, and programming.

• Conclusion: This is known as the modular approach.

429. The errors that can be pointed out by the compiler are:

1. Syntax errors

2. Logical errors

3. Semantic errors

4. Internal errors

Show me the answer

Answer: 1. Syntax errors

Explanation:

• Compiler Errors: Compilers detect syntax errors, which are violations of the programming language's rules.

• Conclusion: Syntax errors are detected by the compiler.

430. The dispatcher:

1. Actually schedules the tasks into the processor

2. Puts tasks in I/O wait

3. Is always small and simple

4. Never changes task priorities

Show me the answer

Answer: 1. Actually schedules the tasks into the processor

Explanation:

• Dispatcher: The dispatcher is responsible for loading the selected process into the CPU for execution.

• Conclusion: The dispatcher schedules tasks into the processor.

431. The SJF algorithm executes first the job:

1. That last entered the queue

2. The first entered the queue

3. That has been in the queue the longest

4. With the least processor needs

Show me the answer

Answer: 4. With the least processor needs

Explanation:

• SJF Scheduling: Shortest Job First (SJF) schedules the job with the shortest execution time first.

• Conclusion: SJF prioritizes jobs with the least processor needs.

432. Semaphores:

1. Synchronize critical resources to prevent deadlock

2. Synchronize critical resources to prevent contention

3. Are used to do I/O

4. Are used for memory management

Show me the answer

Answer: 1. Synchronize critical resources to prevent deadlock

Explanation:

• Semaphores: Semaphores are used to synchronize access to critical resources and prevent deadlock.

• Conclusion: Semaphores prevent deadlock by synchronizing resource access.

433. Fragmentation of the file system:

1. Occurs only if the file system is used improperly

2. Can always be prevented

3. Can be temporarily removed by compaction

4. Is a characteristic of all file systems

Show me the answer

Answer: 3. Can be temporarily removed by compaction

Explanation:

• Fragmentation: Fragmentation occurs when files are stored in non-contiguous blocks. Compaction can temporarily reduce fragmentation.

• Conclusion: Fragmentation can be temporarily removed by compaction.

434. The command interpreter:

1. Is usually the primary user interface

2. Requires fixed format commands

3. Is menu driven

4. Is quite different from the SCL interpreter

Show me the answer

Answer: 1. Is usually the primary user interface

Explanation:

• Command Interpreter: The command interpreter (shell) is the primary user interface in many operating systems.

• Conclusion: The command interpreter is the primary user interface.

435. A translator is best described as:

1. An application software

2. A hardware component

3. A system software

4. All of the above

Show me the answer

Answer: 3. A system software

Explanation:

• Translator: A translator (e.g., compiler, assembler) is a system software that converts high-level or assembly language code into machine code.

• Conclusion: A translator is a system software.

436. The part of the machine-level instruction, which tells the central processor what has to be done, is:

1. Operation code

2. Locator

3. Address

4. Flip-flop

Show me the answer

Answer: 1. Operation code

Explanation:

• Operation Code: The operation code (opcode) specifies the operation to be performed by the CPU.

• Conclusion: The opcode tells the CPU what to do.

437. Which of the following instruction steps would be written within the diamond-shaped box of a flowchart?

1. S = B - C

2. PRINT A

3. IS A < 10

4. DATA X, 4, Z

Show me the answer

Answer: 3. IS A < 10

Explanation:

• Flowchart Diamond: The diamond-shaped box in a flowchart represents a decision or condition, such as "IS A < 10."

• Conclusion: Decision steps are written in diamond-shaped boxes.

438. Block caches or buffer caches are used:

1. To improve disk performance

2. To handle interrupts

3. To increase the capacity of the main memory

4. To speed up main memory read operation

Show me the answer

Answer: 1. To improve disk performance

Explanation:

• Block Caches: Block caches store frequently accessed disk blocks in memory to reduce disk I/O and improve performance.

• Conclusion: Block caches improve disk performance.

439. To avoid the race condition, the maximum number of processes that may be simultaneously inside their critical section is:

1. 8

2. 1

3. 16

4. 0

Show me the answer

Answer: 2. 1

Explanation:

• Race Condition: A race condition occurs when multiple processes access shared resources simultaneously. To avoid this, only one process should be in the critical section at a time.

• Conclusion: Only one process can be in the critical section at a time.

440. What is the initial value of the semaphore to allow only one of the many processes to enter their critical section?

1. 8

2. 1

3. 16

4. 0

Show me the answer

Answer: 2. 1

Explanation:

• Semaphore Initialization: A semaphore initialized to 1 allows only one process to enter the critical section at a time.

• Conclusion: The initial value of the semaphore is 1.

441. Which technique stores a program on disk and then transfers the program into main storage as and when they are needed, is known as:

1. Spooling

2. Thrashing

3. Swapping

4. All of the above

Show me the answer

Answer: 3. Swapping

Explanation:

• Swapping: Swapping involves moving processes between main memory and disk to free up memory for other processes.

• Conclusion: Swapping transfers programs between disk and main storage as needed.

442. Which of the following is not true about the description of a decision table?

1. A decision table is easy to modify

2. A decision table is directly understood by the computer

3. A decision table is easy to understand

4. All of the above

Show me the answer

Answer: 2. A decision table is directly understood by the computer

Explanation:

• Decision Table: A decision table is a tool for representing complex logic in a tabular format. It is not directly understood by the computer but is used by programmers to design logic.

• Conclusion: Decision tables are not directly understood by computers.

443. The memory allocation scheme subject to ‘external’ fragmentation is:

1. Segmentation

2. Pure demand paging

3. Swapping

4. Multiple contiguous fixed partitions

Show me the answer

Answer: 1. Segmentation

Explanation:

• External Fragmentation: Segmentation can lead to external fragmentation, where free memory is divided into small, non-contiguous blocks.

• Conclusion: Segmentation is subject to external fragmentation.

444. The advantage of a command processor running only built-in commands is:

1. Flexibility to the users in running lists of commands by simply collecting them in named batch command files

2. The command set being common across different hardware configurations

3. Users can create system programs and run them as commands

4. The processing is much faster than would otherwise be the case when user-defined commands are used

Show me the answer

Answer: 2. The command set being common across different hardware configurations

Explanation:

• Built-in Commands: Built-in commands are consistent across different hardware configurations, providing a standardized interface.

• Conclusion: Built-in commands ensure a common command set across hardware.

445. Which of the following is not true about memory management?

1. Virtual memory is used only in multiuser systems

2. Segmentation suffers from external fragmentation

3. Paging suffers from internal fragmentation

4. Segmented memory can be paged

Show me the answer

Answer: 1. Virtual memory is used only in multiuser systems

Explanation:

• Virtual Memory: Virtual memory is used in both single-user and multiuser systems to extend the available memory.

• Conclusion: Virtual memory is not limited to multiuser systems.

446. In which way(s) can a macro processor for assembly language be implemented?

1. Independent two-pass processor

2. Independent one-pass processor

3. Processor incorporated into pass 1 of a standard two-pass assembler

4. All of the above

Show me the answer

Answer: 4. All of the above

Explanation:

• Macro Processor Implementation: A macro processor can be implemented as an independent two-pass or one-pass processor or integrated into the assembler.

• Conclusion: All the listed methods are valid.

447. The disadvantage of “Compile and GO” loading scheme is (are):

1. A portion of memory is wasted because the core occupied by the assembler is unavailable to the object program

2. It is necessary to retranslate the user’s program deck every time it is run

3. It is very difficult to handle multiple segments, especially if the source programs are in different languages, and to produce orderly modular programs

4. All of the above

Show me the answer

Answer: 4. All of the above

Explanation:

• Compile and GO: This scheme has several disadvantages, including memory waste, retranslation, and difficulty handling multiple segments.

• Conclusion: All the listed disadvantages apply to the Compile and GO scheme.

448. In analyzing the compilation of a PL/I program, the term “syntax analysis” is associated with:

1. Recognition of basic syntactic constructs through reductions

2. Recognition of basic elements and creation of uniform symbols

3. Creation of more optional matrix

4. Use of macro processor to produce more optimal assembly code

Show me the answer

Answer: 1. Recognition of basic syntactic constructs through reductions

Explanation:

• Syntax Analysis: Syntax analysis involves recognizing the structure of the program and reducing it to basic syntactic constructs.

• Conclusion: Syntax analysis is associated with recognizing syntactic constructs.

449. Uniform Symbols Table:

1. Contains all constants in the program

2. A permanent table of decision rules in the form of patterns for matching with the uniform symbol table to discover syntactic structure

3. Consists of a full or partial list of the tokens as they appear in the program, created by lexical analysis and used for syntax analysis and interpretation

4. A permanent table which lists all keywords and special symbols of the language in symbolic form

Show me the answer

Answer: 3. Consists of a full or partial list of the tokens as they appear in the program, created by lexical analysis and used for syntax analysis and interpretation

Explanation:

• Uniform Symbols Table: This table contains tokens generated by the lexical analyzer and is used during syntax analysis.

• Conclusion: The uniform symbols table consists of tokens used for syntax analysis.

450. The function(s) of the scheduler is (are):

1. It selects which ready process is to be run next

2. It specifies the time slice

3. It is waiting for an event to occur before continuing execution

4. Both A and B

Show me the answer

Answer: 4. Both A and B

Explanation:

• Scheduler Functions: The scheduler selects the next process to run and may specify the time slice for time-sharing systems.

• Conclusion: The scheduler performs both functions.