Which of the following describes combining speech with an RF carrier signal?

Modulation is the process of altering an RF carrier wave in order to transmit information, such as voice, video, or data. By varying the carrier's amplitude, frequency, or phase in step with the audio, the speech signal is successfully embedded onto the radio wave so it can travel through the air. The other options serve entirely different functions in a radio. Impedance matching ensures maximum power transfer between components like a transmitter and an antenna. Oscillation is the generation of the blank carrier wave itself, and filtering simply removes unwanted frequencies.