Answer:
alright, I'm thinking its b. I'm thinking this because, Abraham Lincoln was, as we all know, against slavery. If he was writing this after November 6, 1860, the day he got elected president, he would be writing his stance on the expansion of slavery. He would be doing this, as he wanted to keep the southern states happy, as there was rumor's someone would succeed the union. Stating his stance on the expansion of slavery, in a letter, seems reasonable to me; as i would have been able to better explain the question, if more info was provided.
Really hoped I helped you, if its wrong, im really sorry!
