Which button would you use to play an external stereo source?

To play an external stereo source, the option referring to CR PLAY is the most suitable choice. This button is typically used to control the playback of audio from an external source, such as a CD player, digital audio workstation, or any other stereo input. It functions by directing the audio signals from this external device to the main output, ensuring the sound is transmitted properly to the desired destination.

The other options, such as CTRL PGM and CUT L+R, serve different functions. CTRL PGM is generally used for controlling program outputs rather than directly handling playback from external sources, while CUT L+R typically refers to cutting or muting the left and right channels, which would not facilitate playback. The MAIN button generally refers to the overall main output control, but does not specifically target the external stereo source's playback, making CR PLAY the clear and correct choice for engaging with external audio devices.