What sound is heard from a public address system if audio rectification of a nearby CW transmission occurs?

Continuous Wave (CW) transmissions consist of a pure radio frequency carrier that is simply turned on and off to form Morse code. When this type of signal is subjected to audio rectification in an audio amplifier (like a public address system), there is no voice modulation to be detected. Instead, the turning on and off of the carrier causes sudden changes in the amplifier's bias or picks up ambient power supply noise, manifesting as clicks, thumps, or on-and-off humming. Options suggesting speech or whistling are incorrect because whistling requires a beat frequency oscillator (BFO) in a receiver, and there is no voice audio present in a pure CW signal.