Your answer would be A) How the slave population would be counted. During the time, there was a big debate on whether or not the slaves in the U.S should be counted towards the whole population of the United States when it comes to voting. People wanted a proper number, or representation, of the amount of people in the U.S that voted. The free men that lived in the U.S has every right to vote, but whenever a Slave votes, their votes would count as only 3/5 of a person. That's where the three-fifths compromise comes from, it decided that slaves could only be 3/5 of a person, meaning that their vote will count as 3/5, but not 1 whole. This means that the slaves who vote don't represent a whole person, and is only partially voting. This made the voting numbers very difficult and inaccurate because a person who's voting can't be only 3/5 of a person. In order for the votes to be more accurate, people believed that everyone, even slaves, should be one whole vote, not 3/5 of a vote.
Most European countries were angered with the Monroe Doctrine the United States implemented especially the countries and empires part of the Holy Alliance after the Napoleonic war. But due to insufficient power and naval forces to implement the doctrine most countries disregard the threat.