What is a common format for compressed audio files?

The most common format for compressed audio files is .mp3. This format uses a lossy compression method that significantly reduces the file size of audio tracks while maintaining a level of sound quality that is generally acceptable for casual listening. The .mp3 format is widely supported across various devices and platforms, making it a popular choice for music distribution and personal audio collections.

In contrast, the other formats listed serve different purposes. .zip is a file format used for compressing and archiving multiple files together, not specifically for audio. .png is an image format that uses lossless compression, making it suitable for graphics and photos but not for audio. .exe is an executable file format used for running programs on Windows operating systems and is not related to audio file formats. Thus, .mp3 stands out as the correct choice, specifically designed for compressed audio.