What is digital video primarily composed of?

Digital video is primarily composed of content streams and a file container. The content streams include both the video and audio components, which are essential for creating a complete multimedia experience. The video stream typically contains the visual information in the form of frames, while the audio stream carries sound that syncs with the video.

The file container serves as the wrapper that encapsulates these streams, along with additional metadata and format specifications, allowing the media to be played back seamlessly on various devices and platforms. Common container formats include MP4, AVI, and MOV, each of which supports various codecs for compressing the video and audio streams within them.

In contrast to the other options, audio streams only would not provide the visual component necessary for video, while text documents and graphics pertain to different media types entirely. Film reels and physical media refer to analog formats and storage methods that do not apply in the context of digital video, further emphasizing why content streams and a file container is the correct representation of digital video composition.