IT 110 Computer Operating Systems
Comprehensive Final Exam (Qns & Ans)
2025
Question 1 (Multiple Choice)
Question:
Which of the following best characterizes a microkernel
architecture?
A) All operating system services run in kernel space
B) Only the fundamental functions reside in the kernel while most
services run in user space
C) The entire operating system is packed into a single, non-
modular binary
D) Device drivers are the only components executed in user space
Correct ANS:
B) Only the fundamental functions reside in the kernel while most
services run in user space
©2025
, Rationale:
Microkernel architectures aim to improve modularity and
reliability by moving most operating system services (such as file
systems, network protocols, and device drivers) into user space,
leaving only the minimal necessary functions (like inter-process
communication and basic scheduling) in kernel space. This
separation enhances system stability and security.
---
Question 2 (Fill in the Blank)
Question:
To transfer control from user space to kernel space for servicing a
system call, the operating system typically uses a ________
mechanism.
Correct ANS:
trap
Rationale:
A trap is a synchronous interrupt triggered by a system call, which
safely transitions the execution from user mode to kernel mode.
This mechanism is essential for enforcing protection boundaries
©2025
,and ensuring that privileged operations are executed within the
kernel.
---
Question 3 (True/False)
Question:
True/False: In preemptive multitasking, processes are periodically
interrupted to allow for concurrent execution, which necessitates
careful synchronization to avoid race conditions.
Correct ANS:
True
Rationale:
Preemptive multitasking allows an operating system to interrupt
executing processes, thereby enabling concurrent execution. This
introduces challenges such as race conditions and requires robust
synchronization mechanisms (e.g., locks or semaphores) to
maintain data consistency.
---
©2025
, Question 4 (Multiple Response)
Question:
Select all synchronization primitives commonly used in operating
systems to manage concurrent access to shared resources:
A) Mutexes
B) Semaphores
C) Spinlocks
D) Barriers
E) File descriptors
Correct ANS:
A, B, C, D
Rationale:
Mutexes, semaphores, spinlocks, and barriers are standard
primitives for coordinating access among concurrent processes or
threads, ensuring that critical sections are not executed
simultaneously. File descriptors, however, are handles used for
file I/O rather than direct synchronization tools.
---
©2025
Comprehensive Final Exam (Qns & Ans)
2025
Question 1 (Multiple Choice)
Question:
Which of the following best characterizes a microkernel
architecture?
A) All operating system services run in kernel space
B) Only the fundamental functions reside in the kernel while most
services run in user space
C) The entire operating system is packed into a single, non-
modular binary
D) Device drivers are the only components executed in user space
Correct ANS:
B) Only the fundamental functions reside in the kernel while most
services run in user space
©2025
, Rationale:
Microkernel architectures aim to improve modularity and
reliability by moving most operating system services (such as file
systems, network protocols, and device drivers) into user space,
leaving only the minimal necessary functions (like inter-process
communication and basic scheduling) in kernel space. This
separation enhances system stability and security.
---
Question 2 (Fill in the Blank)
Question:
To transfer control from user space to kernel space for servicing a
system call, the operating system typically uses a ________
mechanism.
Correct ANS:
trap
Rationale:
A trap is a synchronous interrupt triggered by a system call, which
safely transitions the execution from user mode to kernel mode.
This mechanism is essential for enforcing protection boundaries
©2025
,and ensuring that privileged operations are executed within the
kernel.
---
Question 3 (True/False)
Question:
True/False: In preemptive multitasking, processes are periodically
interrupted to allow for concurrent execution, which necessitates
careful synchronization to avoid race conditions.
Correct ANS:
True
Rationale:
Preemptive multitasking allows an operating system to interrupt
executing processes, thereby enabling concurrent execution. This
introduces challenges such as race conditions and requires robust
synchronization mechanisms (e.g., locks or semaphores) to
maintain data consistency.
---
©2025
, Question 4 (Multiple Response)
Question:
Select all synchronization primitives commonly used in operating
systems to manage concurrent access to shared resources:
A) Mutexes
B) Semaphores
C) Spinlocks
D) Barriers
E) File descriptors
Correct ANS:
A, B, C, D
Rationale:
Mutexes, semaphores, spinlocks, and barriers are standard
primitives for coordinating access among concurrent processes or
threads, ensuring that critical sections are not executed
simultaneously. File descriptors, however, are handles used for
file I/O rather than direct synchronization tools.
---
©2025
