351. Which of the following capabilities is required for a system program to execute more than one program at a time?
Word processing
Virtual memory
Compiling
Multitasking
Show me the answer
Answer: 4. Multitasking
Explanation:
Multitasking: Multitasking is the capability of an operating system to execute multiple programs simultaneously by switching between them. This allows efficient utilization of CPU and other resources.
Conclusion: Multitasking is essential for executing multiple programs at the same time.
352. A critical region is:
A program segment that has not been proved bug-free
A program segment that often causes unexpected system crashes
A program segment where shared resources are accessed
One which is enclosed by a pair of P and V operations on semaphores
Show me the answer
Answer: 3. A program segment where shared resources are accessed
Explanation:
Critical Region: A critical region is a segment of code where shared resources are accessed. To prevent race conditions, only one process can execute its critical region at a time.
Conclusion: The critical region is where shared resources are accessed.
353. Which of the following addressing modes facilitates access to an operand whose location is defined relative to the beginning of the data structure in which it appears?
Ascending
Index
Sorting
Indirect
Show me the answer
Answer: 2. Index
Explanation:
Index Addressing Mode: In index addressing mode, the effective address of the operand is calculated by adding a constant value to the contents of a register (index register). This is useful for accessing elements in arrays or data structures.
Conclusion: Index addressing mode facilitates access to operands relative to the beginning of a data structure.
354. The register or main memory location which contains the effective address of the operand is known as:
Pointer
Special location
Indexed register
Scratch pad
Show me the answer
Answer: 1. Pointer
Explanation:
Pointer: A pointer is a register or memory location that holds the effective address of an operand. It is used to indirectly access data.
Conclusion: The register or memory location containing the effective address is called a pointer.
355. System programs such as compilers are designed so that they are:
Re-entrant
Serially usable
Non-reusable
Recursive
Show me the answer
Answer: 1. Re-entrant
Explanation:
Re-entrant Programs: Re-entrant programs can be interrupted in the middle of execution and called again before the previous execution completes. This is essential for system programs like compilers to handle multiple users or tasks.
Conclusion: System programs like compilers are designed to be re-entrant.
356. Special software to create a job queue is called a:
Drive
Interpreter
Spooler
Linkage editor
Show me the answer
Answer: 3. Spooler
Explanation:
Spooler: A spooler is a software component that manages job queues, particularly for printing or other I/O operations. It allows multiple jobs to be queued and processed sequentially.
Conclusion: A spooler creates and manages job queues.
357. The most common security failure is:
Carelessness by users
Depending on passwords
Too much emphasis on preventing physical access
Insufficient technology used to prevent breaches
Show me the answer
Answer: 1. Carelessness by users
Explanation:
Security Failures: The most common security failures are caused by human errors, such as weak passwords, sharing credentials, or falling for phishing attacks.
Conclusion: User carelessness is the primary cause of security failures.
358. A public key encryption system:
Allows anyone to decode the transmission
Allows only the correct sender to decode the data
Allows only the correct receiver to decode the data
Does not encode the data before transmitting it
Show me the answer
Answer: 3. Allows only the correct receiver to decode the data
Explanation:
Public Key Encryption: In public key encryption, the sender uses the receiver's public key to encrypt the data, and only the receiver's private key can decrypt it. This ensures that only the intended receiver can decode the data.
Conclusion: Public key encryption ensures secure communication by allowing only the correct receiver to decode the data.
359. Supervisor state is:
Never used
Entered by programs when they enter the processor
Required to perform any I/O
Only allowed to the operating system
Show me the answer
Answer: 4. Only allowed to the operating system
Explanation:
Supervisor State: The supervisor state (or kernel mode) is a privileged mode of operation where the operating system can execute instructions that are not available to user programs. It is used for critical tasks like memory management and I/O operations.
Conclusion: The supervisor state is restricted to the operating system.
360. A high paging rate:
May cause a high I/O rate
Keeps the system running well
Is a symptom of too much processor activity
Always creates a slow system
Show me the answer
Answer: 1. May cause a high I/O rate
Explanation:
High Paging Rate: A high paging rate indicates frequent page faults, which require data to be read from or written to secondary storage. This increases the I/O rate and can degrade system performance.
Conclusion: A high paging rate may lead to increased I/O activity.
361. Round robin scheduling is essentially the preemptive version of:
FIFO
FILO
FCFS
Longest time first
Show me the answer
Answer: 1. FIFO
Explanation:
Round Robin Scheduling: Round robin scheduling is a preemptive version of FIFO (First-In-First-Out) scheduling. Each process is given a fixed time slice (quantum) to execute, and the CPU switches between processes after each quantum.
Conclusion: Round robin is the preemptive version of FIFO.
362. If the number of bits in the virtual address of a program is 12 and the page size is 0.5 KB, the number of pages in the virtual address space is:
16
32
64
128
Show me the answer
Answer: 4. 128
Explanation:
Virtual Address Space: The virtual address space is determined by the number of bits in the virtual address. For 12 bits, the total addressable space is:
212=4096 bytes
Page Size: The page size is 0.5 KB (512 bytes). The number of pages is:
5124096=8
Conclusion: The number of pages is 8 (assuming a typo in the question).
363. In which of the storage placement strategies is a program placed in the largest available hole in the main memory?
Best fit
Worst fit
First fit
Buddy
Show me the answer
Answer: 2. Worst fit
Explanation:
Worst Fit: The worst fit strategy allocates the largest available hole in memory to a process. This can lead to inefficient memory utilization but may reduce fragmentation in some cases.
Conclusion: Worst fit places a program in the largest available hole.
364. For how many processes which are sharing common data does Dekker’s algorithm implement mutual exclusion?
1
2
3
4
Show me the answer
Answer: 2. 2
Explanation:
Dekker’s Algorithm: Dekker’s algorithm is a mutual exclusion algorithm designed for two processes. It ensures that only one process can enter the critical section at a time.
Conclusion: Dekker’s algorithm works for two processes.
365. A disk scheduling algorithm in an operating system causes the disk arm to move back and forth across the disk surface in order to service all requests in its path. This is a:
First come first served
Scan
Shortest Seek Time First (SSTF)
FIFO
Show me the answer
Answer: 2. Scan
Explanation:
SCAN Algorithm: The SCAN algorithm moves the disk arm in one direction, servicing all requests in its path, and then reverses direction. This reduces seek time and improves efficiency.
Conclusion: The SCAN algorithm causes the disk arm to move back and forth.
366. Round-robin scheduling:
Allows interactive tasks quicker access to the processor
Is quite complex to implement
Gives each task the same chance at the processor
Allows processor-bound tasks more time in the processor
Show me the answer
Answer: 3. Gives each task the same chance at the processor
Explanation:
Round Robin Scheduling: Round robin scheduling provides fair CPU allocation by giving each task an equal time slice (quantum). This ensures that all tasks get an equal chance to execute.
Conclusion: Round robin gives each task the same chance at the processor.
367. Inter-process communication:
Is required for all processes
Is usually done via disk drives
Is never necessary
Allows processes to synchronize activity
Show me the answer
Answer: 4. Allows processes to synchronize activity
Explanation:
Inter-Process Communication (IPC): IPC allows processes to communicate and synchronize their activities. Common IPC mechanisms include shared memory, message passing, and pipes.
Conclusion: IPC enables process synchronization.
368. Fork is:
The dispatching of a task
The creation of a new job
The creation of a new process
Increasing the priority of a task
Show me the answer
Answer: 3. The creation of a new process
Explanation:
Fork: The fork system call creates a new process by duplicating the existing process. The new process is called the child process, and the original process is called the parent process.
Conclusion: Fork is used to create a new process.
369. A process is another name for:
A job
Paging
A task
The operating system dispatcher
Show me the answer
Answer: 3. A task
Explanation:
Process: A process is an instance of a program in execution. It is also referred to as a task in some contexts.
Conclusion: A process is another name for a task.
370. Relocation bits used by relocating loader are specified (generated by):
Relocating loader itself
Assembler or translator
Linker
Macro processor
Show me the answer
Answer: 2. Assembler or translator
Explanation:
Relocation Bits: Relocation bits are generated by the assembler or translator to indicate which parts of the program need to be adjusted during loading.
Conclusion: The assembler or translator generates relocation bits.
371. Device independence:
Allows the computer to run without I/O devices
Makes all devices look the same to the operating system
Allows programs to be written more easily
Allows tape drives to be substituted for disk drives
Show me the answer
Answer: 3. Allows programs to be written more easily
Explanation:
Device Independence: Device independence allows programs to interact with devices without needing to know the specific details of the hardware. This simplifies programming and improves portability.
Conclusion: Device independence makes programming easier.
372. User-Friendly Systems are:
Required for object-oriented programming
Easy to develop
Common among traditional mainframe operating systems
Becoming more common
Show me the answer
Answer: 4. Becoming more common
Explanation:
User-Friendly Systems: Modern operating systems and applications are designed to be user-friendly, with intuitive interfaces and features that make them accessible to a wide range of users.
Conclusion: User-friendly systems are increasingly common.
373. Disk scheduling includes deciding:
Which disk should be accessed next
The order in which disk access requests must be serviced
The physical location of the file
The logical location of the file
Show me the answer
Answer: 2. The order in which disk access requests must be serviced
Explanation:
Disk Scheduling: Disk scheduling determines the order in which disk access requests are serviced to minimize seek time and improve performance.
Conclusion: Disk scheduling focuses on the order of disk access requests.
374. Which of the following translator programs convert assembly language program to object program?
Assembler
Macro processor
Compiler
Linker
Show me the answer
Answer: 1. Assembler
Explanation:
Assembler: An assembler converts assembly language programs into machine code (object programs).
Conclusion: The assembler translates assembly language to object code.
375. Data encryption:
Is mostly used by public networks
Is mostly used by financial networks
Cannot be used by private installations
Is not necessary, since data cannot be intercepted
Show me the answer
Answer: 2. Is mostly used by financial networks
Explanation:
Data Encryption: Data encryption is widely used in financial networks to protect sensitive information during transmission.
Conclusion: Financial networks heavily rely on data encryption.
376. Seeks analysis:
Is used for analyzing paging problems
Is used for analyzing device busy problems
Is used for analyzing control-unit busy problems
Is only shown on real-time displays
Show me the answer
Answer: 2. Is used for analyzing device busy problems
Explanation:
Seeks Analysis: Seeks analysis is used to study and optimize disk access patterns, particularly to address device busy problems.
Answer: 3. Allows each program in turn to use the memory
Explanation:
Swapping: Swapping allows multiple programs to share memory by moving them between main memory and secondary storage. Each program gets a turn to use the memory.
Conclusion: Swapping enables programs to take turns using memory.
378. Feedback queue:
Are very easy to implement
Dispatch tasks according to execution characteristics
Are used to favor real-time tasks
Require manual intervention to implement properly
Show me the answer
Answer: 2. Dispatch tasks according to execution characteristics
Explanation:
Feedback Queue: A feedback queue is a scheduling mechanism that adjusts the priority of tasks based on their execution history. Tasks that use too much CPU time are moved to lower-priority queues.
Conclusion: Feedback queues dispatch tasks based on execution characteristics.
379. A file organization component of a VSAM file is:
Relative record data set
Entry sequential data set
Keyed sequential data set
All of the above
Show me the answer
Answer: 4. All of the above
Explanation:
VSAM File Organization: VSAM (Virtual Storage Access Method) supports multiple file organizations, including relative record, entry sequential, and keyed sequential data sets.
Conclusion: All the given options are components of VSAM file organization.
380. The file structure that redefines its first record at a basic of zero uses the term:
Relative organization
Dynamic reallocation
Key fielding
Hashing
Show me the answer
Answer: 1. Relative organization
Explanation:
Relative Organization: In relative file organization, records are accessed using relative record numbers, starting from zero.
Conclusion: Relative organization redefines the first record at a base of zero.
381. File record length:
Should always be fixed
Should always be variable
Depends upon the size of the file
Should be chosen to match the data characteristics
Show me the answer
Answer: 4. Should be chosen to match the data characteristics
Explanation:
File Record Length: The record length should be chosen based on the characteristics of the data being stored. Fixed or variable record lengths can be used depending on the application.
Conclusion: Record length should match data characteristics.
382. An incremental backup:
Should be done each month
Uses more tapes
Saves all files
Saves only files that have recently changed
Show me the answer
Answer: 4. Saves only files that have recently changed
Explanation:
Incremental Backup: An incremental backup saves only the files that have changed since the last backup. This reduces the amount of data to be backed up and speeds up the process.
Conclusion: Incremental backups save only recently changed files.
383. A partitioned data set is most used for:
Program or source library
Storing backup information
Storing program data
Storing ISAM file
Show me the answer
Answer: 1. Program or source library
Explanation:
Partitioned Data Set (PDS): A PDS is commonly used to store program source code or libraries. It allows multiple members (files) to be stored within a single dataset.
Conclusion: PDS is primarily used for program or source libraries.
384. System generation:
Is always quite simple
Is always very difficult
Varies in difficulty between systems
Requires extensive tools to be understandable
Show me the answer
Answer: 3. Varies in difficulty between systems
Explanation:
System Generation: System generation (sysgen) is the process of configuring and installing an operating system. The difficulty of sysgen varies depending on the complexity of the system and the hardware.
Conclusion: System generation difficulty varies between systems.
385. Object code:
Is ready to execute
Is the output of compilers, but not assemblers
Must be “loaded” before execution
Must be rewritten before execution
Show me the answer
Answer: 3. Must be “loaded” before execution
Explanation:
Object Code: Object code is the output of a compiler or assembler. It is not directly executable and must be linked and loaded into memory before execution.
Conclusion: Object code requires loading before execution.
386. Virtual memory is:
Simple to implement
Used in all major commercial operating systems
Less efficient in utilization of memory
Useful when fast I/O devices are not available
Show me the answer
Answer: 2. Used in all major commercial operating systems
Explanation:
Virtual Memory: Virtual memory is a widely used technique in modern operating systems to manage memory efficiently. It allows processes to use more memory than physically available by swapping data between RAM and secondary storage.
Conclusion: Virtual memory is used in all major commercial operating systems.
387. System maintenance:
Is usually not necessary
Is necessary on all systems, regardless of how good
Is not required if the system is well written
Always requires several programs
Show me the answer
Answer: 2. Is necessary on all systems, regardless of how good
Explanation:
System Maintenance: System maintenance is essential to ensure the continued performance, security, and reliability of a system. It is necessary for all systems, regardless of their initial quality.
Conclusion: System maintenance is necessary for all systems.
388. Which of the following statements is not true?
Time sharing is an example of multiprogramming
JCL is used only to communicate between systems programmers
A batch file contains a series of operating system commands
The primary function of operating systems is to make the computer hardware easily usable
Show me the answer
Answer: 2. JCL is used only to communicate between systems programmers
Explanation:
JCL (Job Control Language): JCL is used to define and control batch jobs in mainframe systems. It is not limited to communication between systems programmers.
Conclusion: The statement about JCL is not true.
389. What scheduling algorithm allows processes that are logically runnable to be temporarily suspended?
Preemptive scheduling
FIFO
Non-preemptive scheduling
FCFS
Show me the answer
Answer: 1. Preemptive scheduling
Explanation:
Preemptive Scheduling: Preemptive scheduling allows the operating system to temporarily suspend a running process and allocate the CPU to another process. This ensures fair CPU allocation and responsiveness.
Conclusion: Preemptive scheduling allows processes to be temporarily suspended.
390. The term ‘polling’ in a computer means a process by which a computer system:
Detects/corrects errors
Multiplexes the inputs and updates the memory accordingly
Decides the correct alternative by analyzing several ones
Inquiries to see if a terminal has any transaction to send
Show me the answer
Answer: 4. Inquiries to see if a terminal has any transaction to send
Explanation:
Polling: Polling is a process where the CPU repeatedly checks the status of devices (e.g., terminals) to see if they have data to send or receive.
Conclusion: Polling involves inquiring about device status.
391. In a magnetic disk, data is recorded in a set of concentric tracks which are subdivided into:
Periods
Zones
Sectors
Groups
Show me the answer
Answer: 3. Sectors
Explanation:
Sectors: A magnetic disk is divided into concentric tracks, which are further subdivided into sectors. Each sector stores a fixed amount of data.
Conclusion: Tracks are subdivided into sectors.
392. Which of the following is true for machine language?
Repeated execution of program segments
Depicting flow of data in a system
A sequence of instructions which, when followed properly, solves a problem
The language which communicates with the computer using only the binary digits 1 and 0
Show me the answer
Answer: 4. The language which communicates with the computer using only the binary digits 1 and 0
Explanation:
Machine Language: Machine language consists of binary instructions that the computer's processor can execute directly. It uses only 1s and 0s to represent instructions and data.
Conclusion: Machine language communicates with the computer using binary digits.
393. The LRU algorithm:
Pages out pages that have been used recently
Pages out pages that have not been used recently
Pages out pages that have been least used recently
Pages out the first page in a given area
Show me the answer
Answer: 3. Pages out pages that have been least used recently
Explanation:
LRU Algorithm: The Least Recently Used (LRU) page replacement algorithm replaces the page that has not been used for the longest time.
Conclusion: LRU pages out the least recently used pages.
394. A linker:
Creates a load module
Is not necessary with variable partitions
Must be run after the loader
Is not needed with a good compiler
Show me the answer
Answer: 1. Creates a load module
Explanation:
Linker: A linker combines object modules into a single load module, resolving external references and preparing the program for execution.
Conclusion: The linker creates a load module.
395. Global locks:
Synchronize access to local resources
Synchronize access to global resources
Are used to avoid local locks
Prevent access to global resources
Show me the answer
Answer: 2. Synchronize access to global resources
Explanation:
Global Locks: Global locks are used to synchronize access to shared resources that are accessed by multiple processes or threads.
Conclusion: Global locks synchronize access to global resources.
396. The dynamic allocation of storage areas with VSAM files is accomplished by:
Hashing
Overflow areas
Control splits
Relative recording
Show me the answer
Answer: 3. Control splits
Explanation:
VSAM Dynamic Allocation: VSAM uses control splits to dynamically allocate storage areas when the dataset grows.
Conclusion: Control splits enable dynamic allocation in VSAM files.
397. Which of the following refers to associative memory?
The address of the data is generated by the CPU
The address of the data is supplied by the user
There is no need for an address, i.e., the data is used as an address
The data are accessed sequentially
Show me the answer
Answer: 3. There is no need for an address, i.e., the data is used as an address
Explanation:
Associative Memory: Associative memory (or content-addressable memory) allows data to be accessed based on its content rather than a specific address.
Conclusion: Associative memory uses data as an address.
398. Link encryption:
Is more secure than end-to-end encryption
Is less secure than end-to-end encryption
Cannot be used in a public network
Is used only to debug
Show me the answer
Answer: 2. Is less secure than end-to-end encryption
Explanation:
Link Encryption: Link encryption encrypts data only over a specific link (e.g., between two nodes). It is less secure than end-to-end encryption, which encrypts data from the source to the destination.
Conclusion: Link encryption is less secure than end-to-end encryption.
399. Which of the following is a characteristic of an operating system?
Resource management
Memory management
Error recovery
All of the above
Show me the answer
Answer: 4. All of the above
Explanation:
Operating System Characteristics: An operating system manages resources, memory, and error recovery, among other tasks.
Conclusion: All the given options are characteristics of an operating system.
400. Files can have:
Read access
Write access
Copy access
All of the above
Show me the answer
Answer: 4. All of the above
Explanation:
File Access: Files can have various access permissions, including read, write, and copy access.
Conclusion: Files can have all the given access types.