Which of the following best describes the function of a transmitter?

The function of a transmitter is to encode information onto a carrier wave. This process involves taking information, which could be audio, video, or data, and modulating it onto a continuous wave that can be effectively radiated through the air. The carrier wave is a radio frequency signal that can be altered in various ways, such as through amplitude or frequency modulation, to represent the information being sent.

This process enables the information to be transmitted over distances, reaching receivers that can demodulate the signal back into its original form. A transmitter is fundamentally designed for the purpose of sending information, making this choice the most accurate description of its core function.

The other options describe different processes or equipment related to radio communication. For instance, receiving radio signals pertains to the function of a receiver, visualizing the frequency spectrum relates to spectrum analyzers, and amplifying incoming signals pertains to the operation of amplifiers or repeaters, rather than the transmission of information.