An abolitionist is someone who is against Slavery and wants to abolish it
C is the main one, but D is also very important (see The Voting Rights Act)
It is probably the partition of India which was the division of British and India in 1947 which eventually created two independent dominions, India and Pakistan.
The anti-federalist felt that the constitution would give too much power to the federal government. They basically were opposed because of what was in it or what wasn't in it because of fear that their civil liberties would be stripped off due to everyone functioning off of the constitution. They more so wanted a bill of rights to proclaim all the liberties a citizen is granted to avoid this.