MOV files from a phone
MOV is Apple's container. Inside, an iPhone recording is usually H.264 or HEVC video with AAC audio, and the audio part is what you are after. Because the audio is already AAC, extracting to M4A is a straight copy — worth choosing if you are heading into an editor rather than a car stereo.
Picking the file on an iPhone
If you are doing this on the phone itself, choose Browse or Files in the picker rather than Photos. Selecting a video from Photos makes iOS export a fresh copy of the whole thing before the browser is even handed the file, which for a long recording means several minutes of waiting with nothing on screen. A file already in Files is handed over immediately.