Answer:
C, to capture the reader's attention.
Usually a story's opening commences with a hook. Furthermore, a hook is a sentence that is used to captivate the reader's attention and awareness. This engages the reader to continue to read more.
A story's opening cannot answer the reader's main questions because it just introduces the story, and the body paragraphs in it will answer them.
It cannot offer clues about the ending, because that is near the finishing of the story, or, in the middle.
A story's opening does not tell the reason of why it was written, that is completely out of the context.