Which of the following is most commonly used to increase 802.

The correct answer is D. Channel width.

According to CompTIA A+ Core 1 220-1201 objectives under Networking and Wireless:

Channel width refers to the size of the frequency band used for Wi-Fi communication.

Increasing channel width (e.g., from 20 MHz to 40 MHz, 80 MHz, or 160 MHz) allows more data to be transmitted at once, effectively increasing wireless throughput speed.

Why the other options are incorrect:

A. Licensed bands: Licensed spectrum is used for certain types of communication and does not directly increase Wi-Fi throughput.

B. Maximum transmission unit (MTU): MTU defines the largest packet size transmitted over a network but is not the primary factor for increasing Wi-Fi throughput.

C. Transmit power: Adjusting transmit power affects signal range and coverage but does not significantly increase throughput; it may improve connectivity but not data rates.