Operating System Questions And Answers - Computer Science MCQ


Computer Science : Operating System

Operating System is the main function-able part of our computer system. The operating system multiple choice questions and answers are discussed as below along with their explanations as necessary.
1. Round robin scheduling is essentially the preemptive version of ________ ?
[B] Shortest job first
[C] Shortest remaining
[D] Longest time first

Answer: A. FIFO


Round-robin (RR) is one of the simplest scheduling algorithms for processes in an operating system.The name of the algorithm comes from the round-robin principle known from other fields, where each person takes an equal share of something in turn.
2. A page fault occurs ?
[A] when the page is not in the memory
[B] when the page is in the memory
[C] when the process enters the blocked state
[D] when the process is in the ready state

Answer: A. when the page is not in the memory


A page fault (sometimes #pf or pf) is a trap to the software raised by the hardware when a program accesses a page that is mapped in the virtual address space, but not loaded in physical memory.
3. Which of the following will determine your choice of systems software for your computer?
[A] Is the applications software you want to use compatible with it ?
[B] Is it expensive ?
[C] Is it compatible with your hardware ?
[D] Both 1 and 3

Answer: D. Both 1 and 3


The choice of the software should be compatible with the hardware and should not be expensive enough.
4. What is a shell ?
[A] is a hardware component
[B] It is a command interpreter
[C] It is a part in compiler
[D] It is a tool in CPU scheduling

Answer: B. It is a command interpreter


A Shell is the command line interpreter that provides the traditional user interface for the UNIX operating system. Users direct the operation of the computer by entering commands as text for a command line interpreter to execute or by creating text scripts of one or more such commands.
5. Routine is not loaded until it is called. All routines are kept on disk in a relocatable load format. The main program is loaded into memory & is executed. This type of loading is called... ?
[A] Static loading
[B] Dynamic loading
[C] Dynamic linking
[D] Overlays

Answer: C. Dynamic linking


Dynamic linking provides the facility to load or unload routines at runtime.
6. In the blocked state ?
[A] the processes waiting for I/O are found
[B] the process which is running is found
[C] the processes waiting for the processor are found
[D] none of the above

Answer: A. the processes waiting for I/O are found


All the processes that are waiting for the completion of some event such as I/O operation or a signal are in Blocked state.
7. What is the memory from 1K - 640K called ?

[A] Extended Memory
[B] Normal Memory
[C] Low Memory
[D] Conventional Memory

Answer: D. Conventional Memory


conventional memory, also called base memory
8. Virtual memory is ..... ?
[A] An extremely large main memory
[B] An extremely large secondary memory
[C] An illusion of extremely large main memory
[D] A type of memory used in super computers

Answer: C. An illusion of extremely large main memory


Virtual memory allows a program to be designed as though there is only one kind of memory, "virtual" memory, which behaves like directly addressable read/write memory (RAM).
9. Which is not the state of the process ?
[A] Blocked
[B] Running
[C] Ready
[D] Privileged

Answer: D. Privileged


The five states of process are:Create , waiting, running, blocked, terminated
10. The number of processes completed per unit time is known as.... ?
[A] Output
[B] Throughput
[C] Efficiency
[D] Capacity

Answer: B. Throughput


The amount of data transferred from one place to another or processed in a specified amount of time is called throughput.

Comments: (Your feedback is valuable to us)

Deb 3 weeks ago Reply

its really helpful for technical exam.thans .

raju kande 1 month ago Reply

This is excellent

usman 3 months ago Reply

70th is D: data inconsistency, not redundancy. redundancy is unusual repetition of data.

Tester 4 months ago Reply


mir mudasir 7 months ago Reply

useful questions for exams

mir mudasir 7 months ago Reply

useful questions for exams

mir mudasir 7 months ago Reply

useful questions for exams

JAMAL 7 months ago Reply

Q 69 answer is wrong at correct answer is option C

sathish 8 months ago Reply

94 th Question answer MULTIPLEXING.. not multiprogramming...

rekha 11 months ago Reply

94th question's answer should be multiprogramming

sathish 8 months ago

That answer is Multiplexing

karthi 11 months ago Reply


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