Expiation: I think that it is between between A or D
Assuming that you're referring to the conflict of cultural disdain between the south and the north,
The author think that the south has race and religious preference, ( white Christian native Americans)
hope this helps
I don't know any of the other similes because I have no idea what poem you read but here is the answer to what growing old like an onion could convey:
Onions are layered, as they grow more and more layers grow. This could mean that as Rachel grows, she gains more layers of knowledge and experiences and they keep layering over time as she grows.
The answer is formal.
hope this helps, have a great day!!