The answer would be D.
The reason behind that is because the Civil War was traumatic and there was so much bloodshed (Like the question states.) If Lincoln believed that it would come back to bite them then the answer would be D. "Until every drop of blood drawn with the lash-", this is talking about the pain of the civil war, "shall be paid by another drawn with the sword.", This quote is stating that with every drop of blood drawn that there would be a punishment for each.