Which of the Following Is True of the Default Attribute

Multiple Choice

Which of the following is true of the default attribute when adding text tracks to a video file?

A) ​It enables all the available tracks by marking them as default.
B) ​It enables the active track by marking it with the default attribute.
C) ​The default attribute is not required when there is a single track available.
D) ​The default attribute is not required when there are multiple tracks available.