WGU D413 Final Exam Review 2026 [Latest]
| Telecommunications & Wireless
Communications | 100% Verified Q&A
Question 1: Which layer of the OSI model is responsible for routing packets between different
networks?
A) Physical Layer
B) Data Link Layer
C) Network Layer
D) Transport Layer
Correct Answer: C) Network Layer
Explanation: The Network Layer (Layer 3) handles routing of packets between different networks,
logical addressing (IP addresses), and path determination. It makes routing decisions based on
network conditions and addressing information.
Question 2: What is the maximum data transfer rate for Bluetooth 5.0?
A) 1 Mbps
B) 2 Mbps
C) 24 Mbps
D) 50 Mbps
Correct Answer: C) 24 Mbps
Explanation: Bluetooth 5.0 offers a maximum data transfer rate of 24 Mbps, which is double the
speed of Bluetooth 4.2. It also provides four times the range and eight times the broadcasting
capacity compared to previous versions.
Question 3: Which multiple access technique divides the frequency spectrum into smaller sub-bands
for different users?
A) TDMA
B) FDMA
C) CDMA
D) SDMA
Correct Answer: B) FDMA
,Explanation: Frequency Division Multiple Access (FDMA) divides the available frequency spectrum
into smaller sub-bands, with each user assigned a specific frequency channel. This allows multiple
users to communicate simultaneously without interference.
Question 4: What is the primary function of a base station in cellular networks?
A) Data encryption
B) Signal amplification
C) Connection between mobile users and the network
D) Power management
Correct Answer: C) Connection between mobile users and the network
Explanation: Base stations serve as the interface between mobile devices and the cellular network
infrastructure. They handle radio communication, call setup, handoff procedures, and connect mobile
users to the core network.
Question 5: Which wireless standard operates in both 2.4 GHz and 5 GHz frequency bands?
A) ZigBee
B) Wi-Fi 6
C) LoRa
D) NFC
Correct Answer: B) Wi-Fi 6
Explanation: Wi-Fi 6 (802.11ax) operates in both 2.4 GHz and 5 GHz frequency bands. It provides
higher data rates, improved efficiency, and better performance in dense environments compared to
previous Wi-Fi standards.
Question 6: What is the typical range of NFC (Near Field Communication)?
A) 10 meters
B) 100 meters
C) 4 cm
D) 1 km
Correct Answer: C) 4 cm
Explanation: NFC operates over very short distances of approximately 4 centimeters. This limited
range provides security benefits for contactless payments and access control applications, making it
difficult for unauthorized interception.
Question 7: Which modulation technique varies the phase of the carrier wave to represent data?
A) ASK
B) FSK
,C) PSK
D) QAM
Correct Answer: C) PSK
Explanation: Phase Shift Keying (PSK) varies the phase of the carrier wave to represent digital data.
Different phase shifts correspond to different bit patterns, allowing efficient data transmission over
wireless channels.
Question 8: What is the main advantage of CDMA over TDMA?
A) Lower power consumption
B) Better voice quality
C) Increased capacity and security
D) Simpler implementation
Correct Answer: C) Increased capacity and security
Explanation: CDMA allows multiple users to share the same frequency band simultaneously using
unique codes. This provides higher capacity, better security through code spreading, and resistance
to interference compared to TDMA.
Question 9: Which cellular generation first introduced packet switching for data transmission?
A) 1G
B) 2G
C) 2.5G
D) 3G
Correct Answer: C) 2.5G
Explanation: 2.5G technologies like GPRS (General Packet Radio Service) introduced packet
switching, allowing efficient data transmission and always-on connectivity for mobile devices,
bridging the gap between 2G and 3G.
Question 10: What is the function of the Mobile Switching Center (MSC) in cellular networks?
A) Radio signal transmission
B) Handset manufacturing
C) Call routing and mobility management
D) Base station maintenance
Correct Answer: C) Call routing and mobility management
Explanation: The MSC handles call setup, routing, and mobility management functions. It connects
calls between mobile users and the public switched telephone network, manages handovers, and
tracks user location.
, Question 11: Which wireless technology is specifically designed for low-power, long-range IoT
applications?
A) Bluetooth
B) Wi-Fi
C) LoRa
D) NFC
Correct Answer: C) LoRa
Explanation: LoRa (Long Range) is designed for low-power, long-range IoT applications. It provides
connectivity over several kilometers while consuming minimal energy, making it ideal for
battery-powered sensors and devices.
Question 12: What is the purpose of frequency hopping in Bluetooth?
A) Increase data rate
B) Reduce power consumption
C) Avoid interference and improve security
D) Extend range
Correct Answer: C) Avoid interference and improve security
Explanation: Bluetooth uses frequency hopping spread spectrum (FHSS) to rapidly switch between
79 frequencies. This reduces interference from other devices and makes interception more difficult,
improving security.
Question 13: Which OSI layer is responsible for error detection and correction in data transmission?
A) Physical Layer
B) Data Link Layer
C) Network Layer
D) Session Layer
Correct Answer: B) Data Link Layer
Explanation: The Data Link Layer (Layer 2) provides error detection and correction, frame
synchronization, and flow control. It ensures reliable data transmission across physical links using
techniques like CRC and ARQ.
Question 14: What is the maximum range of ZigBee in ideal conditions?
A) 10 meters
B) 100 meters
C) 1 kilometer
D) 10 kilometers
Correct Answer: B) 100 meters
| Telecommunications & Wireless
Communications | 100% Verified Q&A
Question 1: Which layer of the OSI model is responsible for routing packets between different
networks?
A) Physical Layer
B) Data Link Layer
C) Network Layer
D) Transport Layer
Correct Answer: C) Network Layer
Explanation: The Network Layer (Layer 3) handles routing of packets between different networks,
logical addressing (IP addresses), and path determination. It makes routing decisions based on
network conditions and addressing information.
Question 2: What is the maximum data transfer rate for Bluetooth 5.0?
A) 1 Mbps
B) 2 Mbps
C) 24 Mbps
D) 50 Mbps
Correct Answer: C) 24 Mbps
Explanation: Bluetooth 5.0 offers a maximum data transfer rate of 24 Mbps, which is double the
speed of Bluetooth 4.2. It also provides four times the range and eight times the broadcasting
capacity compared to previous versions.
Question 3: Which multiple access technique divides the frequency spectrum into smaller sub-bands
for different users?
A) TDMA
B) FDMA
C) CDMA
D) SDMA
Correct Answer: B) FDMA
,Explanation: Frequency Division Multiple Access (FDMA) divides the available frequency spectrum
into smaller sub-bands, with each user assigned a specific frequency channel. This allows multiple
users to communicate simultaneously without interference.
Question 4: What is the primary function of a base station in cellular networks?
A) Data encryption
B) Signal amplification
C) Connection between mobile users and the network
D) Power management
Correct Answer: C) Connection between mobile users and the network
Explanation: Base stations serve as the interface between mobile devices and the cellular network
infrastructure. They handle radio communication, call setup, handoff procedures, and connect mobile
users to the core network.
Question 5: Which wireless standard operates in both 2.4 GHz and 5 GHz frequency bands?
A) ZigBee
B) Wi-Fi 6
C) LoRa
D) NFC
Correct Answer: B) Wi-Fi 6
Explanation: Wi-Fi 6 (802.11ax) operates in both 2.4 GHz and 5 GHz frequency bands. It provides
higher data rates, improved efficiency, and better performance in dense environments compared to
previous Wi-Fi standards.
Question 6: What is the typical range of NFC (Near Field Communication)?
A) 10 meters
B) 100 meters
C) 4 cm
D) 1 km
Correct Answer: C) 4 cm
Explanation: NFC operates over very short distances of approximately 4 centimeters. This limited
range provides security benefits for contactless payments and access control applications, making it
difficult for unauthorized interception.
Question 7: Which modulation technique varies the phase of the carrier wave to represent data?
A) ASK
B) FSK
,C) PSK
D) QAM
Correct Answer: C) PSK
Explanation: Phase Shift Keying (PSK) varies the phase of the carrier wave to represent digital data.
Different phase shifts correspond to different bit patterns, allowing efficient data transmission over
wireless channels.
Question 8: What is the main advantage of CDMA over TDMA?
A) Lower power consumption
B) Better voice quality
C) Increased capacity and security
D) Simpler implementation
Correct Answer: C) Increased capacity and security
Explanation: CDMA allows multiple users to share the same frequency band simultaneously using
unique codes. This provides higher capacity, better security through code spreading, and resistance
to interference compared to TDMA.
Question 9: Which cellular generation first introduced packet switching for data transmission?
A) 1G
B) 2G
C) 2.5G
D) 3G
Correct Answer: C) 2.5G
Explanation: 2.5G technologies like GPRS (General Packet Radio Service) introduced packet
switching, allowing efficient data transmission and always-on connectivity for mobile devices,
bridging the gap between 2G and 3G.
Question 10: What is the function of the Mobile Switching Center (MSC) in cellular networks?
A) Radio signal transmission
B) Handset manufacturing
C) Call routing and mobility management
D) Base station maintenance
Correct Answer: C) Call routing and mobility management
Explanation: The MSC handles call setup, routing, and mobility management functions. It connects
calls between mobile users and the public switched telephone network, manages handovers, and
tracks user location.
, Question 11: Which wireless technology is specifically designed for low-power, long-range IoT
applications?
A) Bluetooth
B) Wi-Fi
C) LoRa
D) NFC
Correct Answer: C) LoRa
Explanation: LoRa (Long Range) is designed for low-power, long-range IoT applications. It provides
connectivity over several kilometers while consuming minimal energy, making it ideal for
battery-powered sensors and devices.
Question 12: What is the purpose of frequency hopping in Bluetooth?
A) Increase data rate
B) Reduce power consumption
C) Avoid interference and improve security
D) Extend range
Correct Answer: C) Avoid interference and improve security
Explanation: Bluetooth uses frequency hopping spread spectrum (FHSS) to rapidly switch between
79 frequencies. This reduces interference from other devices and makes interception more difficult,
improving security.
Question 13: Which OSI layer is responsible for error detection and correction in data transmission?
A) Physical Layer
B) Data Link Layer
C) Network Layer
D) Session Layer
Correct Answer: B) Data Link Layer
Explanation: The Data Link Layer (Layer 2) provides error detection and correction, frame
synchronization, and flow control. It ensures reliable data transmission across physical links using
techniques like CRC and ARQ.
Question 14: What is the maximum range of ZigBee in ideal conditions?
A) 10 meters
B) 100 meters
C) 1 kilometer
D) 10 kilometers
Correct Answer: B) 100 meters
