Answer:
D.
Step-by-step 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.