How does a broadcast transmitter function?

A broadcast transmitter plays a crucial role in the communication process by converting audio and video signals into radio waves. This conversion is essential because while audio and video signals can be used for production and playback, they need to be transformed into a format suitable for transmission over the air to reach receivers such as radios and televisions.

The process involves several steps, including modulation where the audio and video signals are embedded onto specific carrier frequencies. This allows broadcasters to send out signals that can be interpreted by home receivers, facilitating live broadcasts of television programs, music, news, and other content.

In contrast, amplifying audio signals focuses solely on improving sound quality and does not involve transmission. Recording live programming is unrelated to the functioning of a transmitter and is instead a task for production equipment. Lastly, while modulation for digital transmission does occur, the broader and more encompassing function is the conversion of signals into radio waves for overall transmission, which is what makes choice B the most accurate.