Kashmir Civil Services Academy – Operating System MCQs

Kashmir Civil Services Academy

Operating System MCQs (With Answers & Explanations)

1. What is an Operating System?

A. Application software
B. System software
C. Hardware device
D. Programming language
Correct Answer: B
Explanation: OS is system software that manages hardware and software resources.

2. Which of the following is NOT an operating system?

A. Windows
B. Linux
C. MS Word
D. Android
Correct Answer: C
Explanation: MS Word is application software.

3. The main function of an OS is to?

A. Manage hardware
B. Run applications
C. Provide user interface
D. All of the above
Correct Answer: D
Explanation: OS performs all listed functions.

4. Which OS is open source?

A. Windows
B. Linux
C. macOS
D. DOS
Correct Answer: B
Explanation: Linux is open-source software.

5. Which OS is used in smartphones?

A. DOS
B. UNIX
C. Android
D. Windows XP
Correct Answer: C
Explanation: Android is designed for mobile devices.

6. Which OS was developed by Microsoft?

A. Linux
B. UNIX
C. Windows
D. Android
Correct Answer: C
Explanation: Windows is a Microsoft OS.

7. Which OS is used for multitasking?

A. Batch OS
B. Real-time OS
C. Multitasking OS
D. Single-user OS
Correct Answer: C
Explanation: Multitasking OS runs multiple programs simultaneously.

8. Which OS is command-line based?

A. Windows
B. Linux GUI
C. DOS
D. Android
Correct Answer: C
Explanation: DOS uses command-line interface.

9. GUI stands for?

A. Graphical User Interface
B. General User Interface
C. Global User Interface
D. Graphic Utility Interface
Correct Answer: A
Explanation: GUI allows graphical interaction.

10. Which OS manages memory, files, and processes?

A. Compiler
B. BIOS
C. Operating System
D. Application software
Correct Answer: C
Explanation: OS handles core system resources.

11. UNIX is a?

A. Single-user OS B. Multi-user OS C. Batch OS D. Embedded OS
Correct Answer: B
UNIX supports multiple users.

12. Which OS is used in supercomputers?

A. DOS B. UNIX/Linux C. Windows XP D. Android
Correct Answer: B
Linux/UNIX dominate supercomputing.

13. Which OS supports real-time processing?

A. Batch OS B. Real-time OS C. Single-user OS D. Desktop OS
Correct Answer: B
RTOS responds instantly.

14. Which OS was first developed?

A. Windows B. DOS C. Linux D. Android
Correct Answer: B
DOS was an early OS.

15. Kernel is the?

A. Outer layer B. Core of OS C. Application D. Hardware
Correct Answer: B
Kernel is the heart of OS.

16. Which OS is portable?

A. Windows B. Linux C. DOS D. BIOS
Correct Answer: B
Linux runs on many platforms.

17. Which OS supports multiprocessing?

A. Single-user OS B. Multiprocessing OS C. Batch OS D. DOS
Correct Answer: B
Multiprocessing OS uses multiple CPUs.

18. Which OS is text-based?

A. Windows B. macOS C. DOS D. Android
Correct Answer: C
DOS uses text commands.

19. Which OS controls I/O devices?

A. Application B. OS C. Compiler D. User
Correct Answer: B
OS manages input-output.

20. Which OS is free?

A. Windows B. Linux C. macOS D. DOS
Correct Answer: B
Linux is free and open source.

21. Process scheduling is done by?

A. Compiler B. OS C. BIOS D. User
Correct Answer: B
OS schedules CPU time.

22. Which scheduling is simplest?

A. Round Robin B. FCFS C. Priority D. SJF
Correct Answer: B
First Come First Serve is simple.

23. Deadlock occurs when?

A. CPU idle B. Processes wait indefinitely C. Memory full D. OS crashes
Correct Answer: B
Deadlock causes infinite waiting.

24. Which avoids deadlock?

A. FCFS B. Banker’s Algorithm C. Paging D. Segmentation
Correct Answer: B
Banker’s algorithm prevents deadlock.

25. Paging is related to?

A. CPU B. Memory C. Disk D. I/O
Correct Answer: B
Paging manages memory.

26. Virtual memory uses?

A. RAM only B. Cache C. Hard disk D. Register
Correct Answer: C
Disk acts as extended RAM.

27. Thrashing occurs due to?

A. CPU failure B. Excessive paging C. Virus D. Hardware fault
Correct Answer: B
Too much paging reduces performance.

28. File system organizes?

A. CPU B. Memory C. Files D. Devices
Correct Answer: C
File system manages files.

29. Which OS uses FAT?

A. Linux B. DOS C. UNIX D. macOS
Correct Answer: B
DOS uses FAT file system.

30. Multithreading means?

A. Multiple users B. Multiple processes C. Multiple threads D. Multiple OS
Correct Answer: C
Threads run within a process.

31. Semaphore is used for?

A. Scheduling B. Synchronization C. Paging D. Security
Correct Answer: B
Semaphores control access.

32. Which OS supports time-sharing?

A. Batch OS B. Time-sharing OS C. Embedded OS D. DOS
Correct Answer: B
Time-sharing allows multiple users.

33. Device driver is?

A. Hardware B. Software C. Firmware D. Application
Correct Answer: B
Drivers control devices.

34. Which OS is embedded?

A. Android B. RTOS C. Windows D. Linux
Correct Answer: B
RTOS used in embedded systems.

35. Context switching is?

A. Process change B. User change C. Memory change D. Disk change
Correct Answer: A
CPU switches between processes.

36. Which OS uses shell?

A. Windows B. Linux C. Android D. DOS
Correct Answer: B
Linux uses shell.

37. Booting is?

A. Shutting down B. Restarting OS C. Starting OS D. Installing OS
Correct Answer: C
Booting starts OS.

38. Which OS supports GUI?

A. DOS B. Windows C. Assembly D. BIOS
Correct Answer: B
Windows uses GUI.

39. Which manages deadlocks?

A. Hardware B. OS C. User D. Compiler
Correct Answer: B
OS handles deadlocks.

40. Which OS is secure?

A. DOS B. Linux C. Windows 95 D. None
Correct Answer: B
Linux is more secure.

41. Kernel communicates with?

A. Hardware B. User C. Application D. Internet
Correct Answer: A
Kernel interacts with hardware.

42. Which OS is real-time?

A. Windows B. Linux C. RTOS D. DOS
Correct Answer: C
RTOS is real-time.

43. Zombie process is?

A. Running B. Waiting C. Terminated D. Blocked
Correct Answer: C
Zombie is terminated but not removed.

44. Starvation occurs when?

A. CPU idle B. Process never gets CPU C. Memory full D. OS crash
Correct Answer: B
Starvation denies CPU.

45. Which OS is portable?

A. DOS B. Linux C. BIOS D. Windows 95
Correct Answer: B
Linux is portable.

46. Which OS supports multiprocessing?

A. Single-user B. Multi-user C. Multiprocessing D. Batch
Correct Answer: C
Multiprocessing OS uses multiple CPUs.

47. Which OS is fastest?

A. Batch OS B. RTOS C. Desktop OS D. Single-user
Correct Answer: B
RTOS has fastest response.

48. OS is loaded into?

A. ROM B. RAM C. Cache D. Register
Correct Answer: B
OS runs from RAM.

49. Which OS manages security?

A. User B. OS C. Hardware D. Compiler
Correct Answer: B
OS enforces security.

50. OS acts as?

A. Interface B. Hardware C. Application D. Virus
Correct Answer: A
OS is interface between user & hardware.