WGU D413 PRACTICE EXAM BANK – 200 QUESTIONS
WITH VERIFICATIONS & RATIONALES (2026 UPDATE
OA V1 & V2)
This premium study resource contains 200 high-yield,
verified practice questions designed to help you pass the
WGU D413 Objective Assessment (OA V1 & V2) on your
very first attempt. Every question features an italicized
correct answer paired with a bolded rationale to ensure
you master tricky concepts like OSI protocols,
multiplexing, and wireless standards. It is formatted
directly for quick memorization and seamless integration
into flashcard
OSI Model & Network Protocols
,1. Which layer of the OSI model handles end-to-
end flow control, error detection, and reliable
data delivery via retransmissions?
A) Network Layer
B) Data Link Layer
C) Transport Layer
D) Session Layer
Answer: C) Transport Layer
Rationale: The Transport Layer (Layer 4)
manages end-to-end communication control,
ensuring packets arrive error-free, in
sequence, and without loss using protocols
like TCP.
,2. An administrator needs to segment a local
network to isolate broadcast traffic. Which
device or technology operates at Layer 3 to
accomplish this?
A) Layer 2 Switch
B) Network Router
C) Multi-port Repeater
D) Transparent Bridge
Answer: B) Network Router
Rationale: Routers operate at the Network
Layer (Layer 3) and block broadcast traffic
by default, isolating broadcast domains.
Switches only isolate collision domains.
, 3. What protocol is used to resolve a known logical
IPv4 address into a local physical hardware
MAC address?
A) DNS
B) DHCP
C) ARP
D) ICMP
Answer: C) ARP
Rationale: Address Resolution Protocol
(ARP) works at the Data Link Layer to map a
known Layer 3 logical IP address to a Layer 2
physical MAC address.
4. Which standard specifies frame tagging within
Virtual Local Area Networks (VLANs) to
WITH VERIFICATIONS & RATIONALES (2026 UPDATE
OA V1 & V2)
This premium study resource contains 200 high-yield,
verified practice questions designed to help you pass the
WGU D413 Objective Assessment (OA V1 & V2) on your
very first attempt. Every question features an italicized
correct answer paired with a bolded rationale to ensure
you master tricky concepts like OSI protocols,
multiplexing, and wireless standards. It is formatted
directly for quick memorization and seamless integration
into flashcard
OSI Model & Network Protocols
,1. Which layer of the OSI model handles end-to-
end flow control, error detection, and reliable
data delivery via retransmissions?
A) Network Layer
B) Data Link Layer
C) Transport Layer
D) Session Layer
Answer: C) Transport Layer
Rationale: The Transport Layer (Layer 4)
manages end-to-end communication control,
ensuring packets arrive error-free, in
sequence, and without loss using protocols
like TCP.
,2. An administrator needs to segment a local
network to isolate broadcast traffic. Which
device or technology operates at Layer 3 to
accomplish this?
A) Layer 2 Switch
B) Network Router
C) Multi-port Repeater
D) Transparent Bridge
Answer: B) Network Router
Rationale: Routers operate at the Network
Layer (Layer 3) and block broadcast traffic
by default, isolating broadcast domains.
Switches only isolate collision domains.
, 3. What protocol is used to resolve a known logical
IPv4 address into a local physical hardware
MAC address?
A) DNS
B) DHCP
C) ARP
D) ICMP
Answer: C) ARP
Rationale: Address Resolution Protocol
(ARP) works at the Data Link Layer to map a
known Layer 3 logical IP address to a Layer 2
physical MAC address.
4. Which standard specifies frame tagging within
Virtual Local Area Networks (VLANs) to
