Which statement about AAC files is true?

• A. They are the most widely used format for video encoding.
• B. They are used by Apple computers for high-quality audio, but with large file sizes.
• C. They produce the smallest possible file sizes among audio formats.
• D. They are designed for lossless audio only.

Answer: (B)

Advanced Audio Coding (AAC) is a lossy audio format that Apple uses widely for high-quality sound on iTunes and on iPhone, iPad, and Mac devices. The idea behind this statement is that AAC is the codec Apple leans on to deliver good audio quality while keeping file sizes reasonable. In practice, AAC often gives better sound than older formats like MP3 at similar bitrates, which is why Apple favors it for music and streaming. The note about large file sizes isn’t a defining trait of AAC—it's chosen specifically to balance quality and compression, producing smaller files than uncompressed audio for the same perceived quality. Remember, AAC is lossy, not lossless, and it’s an audio format, not a video format.