WGU D686 Operating Systems OA Exam
Practice Exam Questions and Correct Answers
(Verified Answers) Plus Rationales 2026 Q&A |
Instant Download Pdf
1. Which primary function does an operating system perform?
A. Compiles application source code
B. Creates network hardware
C. Manages computer hardware and software resources
D. Designs databases
Rationale: The operating system (OS) acts as an intermediary between
hardware and applications. It manages CPU scheduling, memory
allocation, storage devices, input/output operations, security, and user
interaction while providing services that allow applications to function
efficiently.
2. Which component of an operating system directly manages the
CPU, memory, and hardware devices?
,A. Shell
B. Kernel
C. File explorer
D. Application manager
Rationale: The kernel is the core of the operating system. It operates in
privileged mode, controls hardware resources, schedules processes,
manages memory, and provides essential services to software running
on the system.
3. Which scheduling algorithm executes processes in the order they
arrive?
A. Round Robin
B. First-Come, First-Served (FCFS)
C. Priority Scheduling
D. Shortest Remaining Time
Rationale: FCFS schedules jobs based solely on arrival time. It is simple
to implement but may lead to long waiting times when lengthy jobs
arrive before shorter ones.
4. What is the primary purpose of virtual memory?
,A. Increase processor speed
B. Improve monitor resolution
C. Allow systems to use disk space as an extension of RAM
D. Replace the BIOS
Rationale: Virtual memory extends available memory by using storage
devices to temporarily hold inactive memory pages. This allows more
applications to run simultaneously than physical RAM alone could
support.
5. Which memory management technique divides memory into fixed-
size blocks?
A. Segmentation
B. Paging
C. Swapping
D. Fragmentation
Rationale: Paging divides both physical memory and logical memory
into equal-sized blocks called pages and frames. This simplifies
allocation and eliminates external fragmentation.
, 6. Which state indicates that a process is waiting for an event to
occur?
A. Running
B. Ready
C. Waiting (Blocked)
D. Terminated
Rationale: A blocked process cannot continue execution until an event
such as I/O completion or resource availability occurs. It is temporarily
removed from CPU consideration.
7. What is a context switch?
A. Installing a new operating system
B. Encrypting memory contents
C. Saving one process state and loading another
D. Copying files
Rationale: During a context switch, the operating system saves the CPU
state of the currently running process and restores the state of another
process, allowing multitasking.
8. Which scheduling algorithm gives every process a fixed time slice?
Practice Exam Questions and Correct Answers
(Verified Answers) Plus Rationales 2026 Q&A |
Instant Download Pdf
1. Which primary function does an operating system perform?
A. Compiles application source code
B. Creates network hardware
C. Manages computer hardware and software resources
D. Designs databases
Rationale: The operating system (OS) acts as an intermediary between
hardware and applications. It manages CPU scheduling, memory
allocation, storage devices, input/output operations, security, and user
interaction while providing services that allow applications to function
efficiently.
2. Which component of an operating system directly manages the
CPU, memory, and hardware devices?
,A. Shell
B. Kernel
C. File explorer
D. Application manager
Rationale: The kernel is the core of the operating system. It operates in
privileged mode, controls hardware resources, schedules processes,
manages memory, and provides essential services to software running
on the system.
3. Which scheduling algorithm executes processes in the order they
arrive?
A. Round Robin
B. First-Come, First-Served (FCFS)
C. Priority Scheduling
D. Shortest Remaining Time
Rationale: FCFS schedules jobs based solely on arrival time. It is simple
to implement but may lead to long waiting times when lengthy jobs
arrive before shorter ones.
4. What is the primary purpose of virtual memory?
,A. Increase processor speed
B. Improve monitor resolution
C. Allow systems to use disk space as an extension of RAM
D. Replace the BIOS
Rationale: Virtual memory extends available memory by using storage
devices to temporarily hold inactive memory pages. This allows more
applications to run simultaneously than physical RAM alone could
support.
5. Which memory management technique divides memory into fixed-
size blocks?
A. Segmentation
B. Paging
C. Swapping
D. Fragmentation
Rationale: Paging divides both physical memory and logical memory
into equal-sized blocks called pages and frames. This simplifies
allocation and eliminates external fragmentation.
, 6. Which state indicates that a process is waiting for an event to
occur?
A. Running
B. Ready
C. Waiting (Blocked)
D. Terminated
Rationale: A blocked process cannot continue execution until an event
such as I/O completion or resource availability occurs. It is temporarily
removed from CPU consideration.
7. What is a context switch?
A. Installing a new operating system
B. Encrypting memory contents
C. Saving one process state and loading another
D. Copying files
Rationale: During a context switch, the operating system saves the CPU
state of the currently running process and restores the state of another
process, allowing multitasking.
8. Which scheduling algorithm gives every process a fixed time slice?
