Why do most solid-state transmitters reduce output power as SWR increases beyond a certain level?

Answer: A. To protect the RF output amplifier transistors

High SWR sends reflected power back into the transmitter, which can overheat and damage its output transistors. Most solid-state radios reduce power automatically to protect those RF output amplifier transistors. Lowering power does not lower the SWR itself.

Tip: Power drops to save the final transistors.