What is the action of separating low frequency audio or video signals from a higher frequency carrier called?

The correct answer is detection, which refers to the process of extracting the original low frequency audio or video signal from a higher frequency carrier wave. This process is essential in telecommunications and broadcasting, where information is typically transmitted over long distances using high-frequency carriers to efficiently send data. Detection effectively demodulates the carrier wave, allowing the receiver to retrieve the intended signal for playback or further processing.

In the context of communication systems, detection involves identifying the specific characteristics of the signal, such as its amplitude, frequency, and phase, which enables the reconstruction of the original information. This process is crucial for ensuring that the information sent is accurately received and understood.