Answer:
The answer would be A. To convey background information
Step-by-step explanation:
The reason why I would say that's it's A is because first of all, I'm personally doing a summary of a book at the moment and they've said that it's for background information without really telling exactly what happens in the story. Second, I've actually done research on this exact question and this is what I've found a few days ago: "You might use summary to provide background, set the stage, or illustrate supporting evidence, but keep it very brief: a few sentences should do the trick. Most of your paper should focus on your argument."
Hope this helps