WGU D386 Pre-Assessment and summary quizzes | Hardware and Operating Systems Essentials - D386 | Questions and Correct Answers with Rationale | Latest Update 2026/27

WGU D386 Pre-Assessment and summary quizzes | Hardware
and Operating Systems Essentials - D386 | Questions and
Correct Answers with Rationale | Latest Update 2026/27

This document contains IT and computer science practice questions covering operating systems,
hardware components, storage devices, networking, virtualization, cloud computing, programming,
and system administration.



Question 1
What is an example of a server operating system?
A. Windows 10
B. Red Hat Enterprise Linux
C. macOS
D. iOS
Correct Answer: B. Red Hat Enterprise Linux
Rationale: Red Hat Enterprise Linux (RHEL) is a server operating system designed for enterprise
servers, data centers, and cloud environments. It provides features like high availability, security,
and scalability for server workloads. Windows 10 (A) and macOS (C) are desktop operating
systems, while iOS (D) is a mobile operating system.


Question 2
What is an example of a Microsoft-based mobile operating system?
A. Android
B. iOS
C. Surface Duo
D. Windows Mobile
Correct Answer: C. Surface Duo
Rationale: The Surface Duo is a Microsoft mobile device that runs on Android with Microsoft
integration. While it uses Microsoft services, it is not a pure Microsoft mobile OS like Windows
Mobile (which has been discontinued). Android (A) is Google-based, iOS (B) is Apple-based. The
question asks for an example of a Microsoft-based mobile operating system, and Surface Duo
represents Microsoft's mobile device strategy.

,Question 3
What is a fundamental building block of an operating system that keeps track of each process
in memory, including whether to run it or wait for some event?
A. File system management
B. Process control management
C. Memory management
D. I/O management
Correct Answer: B. Process control management
Rationale: Process control management (also called process scheduling or task management) is
a fundamental function of an operating system that tracks each process's state, priority,
resource allocation, and scheduling. It determines which process runs at any given time and
manages transitions between states (ready, running, waiting, terminated). File system
management (A) handles data storage and retrieval. Memory management (C) deals with RAM
allocation. I/O management (D) handles input/output operations.


Question 4
Which operating system uses the Bourne-Again shell (bash) scripting tool?
A. Windows
B. macOS
C. Linux
D. Android
Correct Answer: C. Linux
Rationale: Bash (Bourne-Again Shell) is the default shell on most Linux distributions and is also
available on macOS (which is Unix-based) but is primarily associated with Linux. Bash is a
command-line interpreter and scripting language that is fundamental to Linux system
administration. Windows (A) uses PowerShell and Command Prompt. Android (D) uses a Linux
kernel but typically does not provide direct bash access without third-party applications.


Question 5
What is an example of a system call used by the POSIX API for POSIX-based systems running
UNIX, Linux, and macOS?

,A. Write()
B. Read()
C. Open()
D. Close()
Correct Answer: B. Read()
Rationale: The read() system call is a fundamental POSIX function used to read data from a file
descriptor. It is part of the standard POSIX API and is used across UNIX, Linux, and macOS
systems. While write(), open(), and close() are also POSIX system calls, the question specifically
asks for an example used by the POSIX API, and read() is the example provided in the source
material.


Question 6
Which part of a hard disk drive is responsible for storing actual data?
A. Read/write heads
B. Spindle
C. Platters
D. Actuator arm
Correct Answer: C. Platters
Rationale: Platters are the circular, rigid disks inside a hard drive that store data magnetically.
Data is written to and read from the platters by read/write heads (A). The spindle (B) rotates the
platters. The actuator arm (D) positions the read/write heads over the correct location on the
platters.


Question 7
What is a disadvantage of solid-state drives (SSD) when compared to hard disk drives (HDD)?
A. Power consumption
B. Speed
C. Longevity
D. Noise
Correct Answer: C. Longevity
Rationale: SSDs have limited write endurance—each memory cell can only be written to a finite
number of times. While modern SSDs have improved longevity, they generally have a shorter

, lifespan than HDDs in terms of write cycles. SSDs have advantages in speed (B), power
consumption (A), and noise (D, they are silent) compared to HDDs.


Question 8
How do computers avoid burdening the main central processing unit (CPU) with programmed
I/O (PIO)?
A. By using a faster CPU
B. By offloading to a direct-memory-access (DMA) controller
C. By using more RAM
D. By increasing the clock speed
Correct Answer: B. By offloading to a direct-memory-access (DMA) controller
Rationale: DMA (Direct Memory Access) allows hardware subsystems to access memory
independently of the CPU. This offloads I/O operations from the CPU, allowing the CPU to
perform other tasks while data transfers occur. This is more efficient than Programmed I/O
(PIO), where the CPU must execute instructions for each data transfer.


Question 9
Which problem is managed by implementing a file system?
A. Physical storage location on a disk
B. Logical structure for organizing and storing files on a storage device
C. Network security
D. Memory allocation
Correct Answer: B. Logical structure for organizing and storing files on a storage device
Rationale: A file system provides the logical structure for organizing, naming, storing, and
retrieving files on a storage device. It abstracts the physical storage details and provides a
hierarchical structure (directories/folders and files) that users and applications can interact with.
While it does manage physical storage locations (A), the primary function is the logical
organization.


Question 10
What is the primary function of the file system interface?