Which of the following is a low voltage level that comes out of a microphone when someone speaks into it?

A microphone converts sound waves into electrical signals, which are characterized by a very low voltage output. This low voltage level is referred to as mic level. When someone speaks into a microphone, the resulting signal is not strong enough to drive speakers directly; it needs to be amplified to a higher level suitable for processing or output.

Mic level signals typically range from -60 to -40 dBu, making them significantly lower than line level signals, which are around -10 dBu for consumer devices and +4 dBu for professional audio equipment. Speaker level signals, on the other hand, are much higher voltage outputs designed for driving the speakers directly. Digital signals are a representation of audio data in binary form, which is different from the analog signals produced by microphones.

Thus, mic level is the correct choice because it accurately describes the output signal voltage level from a microphone when in use.