Which term refers to the way information is encoded into a radio signal?

Question

modulation
frequency
amplitude
spectrum

Answer 1

modulation

Answer 2

amplitude modulatoin

Answer 3

Amplitude modulation (AM) is a method of modulating a radio wave where the amplitude (strength) of the signal varies in proportion to the original message being transmitted (such as voice or music). An AM radio station uses amplitude modulation to encode the audio signal onto a carrier wave, which is then transmitted through the air and decoded by a receiver to reproduce the original audio.