Which of the following best describes signal processing?

Signal processing encompasses a range of activities that modify or manipulate signals within audio-visual systems. The term broadly refers to the techniques used to enhance, analyze, or transform the audio and video signals being transmitted.

Routing audio signals is a key aspect of signal processing since it involves directing these signals through various pathways or devices to achieve the intended audio output. This is crucial in AV environments where different audio sources must be managed effectively.

Adjusting device settings pertains to fine-tuning the parameters of audio and video equipment to optimize performance. This can include changing levels, EQ settings, and other adjustments that are essential for achieving the desired quality in signal outputs.

Formatting video content also falls under the umbrella of signal processing. This includes converting video signals into different formats or resolutions that are compatible with various display technologies, thus ensuring that content is presented correctly regardless of the platform.

Considering that signal processing includes routing, adjusting settings, and formatting, the option indicating "all of the above" accurately reflects the comprehensive nature of the concept within audio-visual practice. Each of these activities contributes to the overall goal of maintaining high-quality audio and video signals in AV systems.