Question

1. what kinds of waves are digitized on a dvd?

Explanation:

DVDs digitize audio and video signals. Audio is originally in the form of sound - waves and video is related to light - waves. But in the context of what is digitized on a DVD, we mainly consider audio (sound) and video (light - related) waves. Sound waves are converted into digital data for audio content and light - related information (images) is digitized for video content.

Answer:

Sound waves and light - related waves (for video)