In the Prologue, the Chorus A provides a musical interlude.
B provides comic relief.
C offers insight into the characters.
D introduces the story line.

D.

Explanation:

Well, I can asnwer this with common sense without knowing what you watched or read. A Prologue is the very first part of a story, kind of an explanation before the actual story starts. So comic relief wouldn't be right because what would you need relief from when the story hasn't started? Music interlude from what? The only option that makes sense is introduces the story line because that's the purpose of a Prologue in the first place.

the correct answer is the following.

one of the groups i belong to is the boy scouts. this is a problem-solving group because it has tasks that we need to solve in order to other people in different activities such as the rescue of lost pets, or elder people in need.

the other group i belong to is kids pro environment, and is an information-sharing group that tries to create conscience about the risks and problems that generate pollution in our cities. we share information to other students and parents on the importance of keep our communities clean and our skies clear.  

the switch in narration increases the proximity of the narrator to the main character and the reader can perceive information only through the filter of a single character.