In debates leading up to the Three-Fifths Compromise, northern states argued that: O A. slaves should be able to buy their freedom after working for a certain number of years. B. slaves should not be included when counting a state's population to determine representation in Congress. c. southern states should only be allowed to send representatives to the House of Representatives, not to the Senate. D. a strong federal government was necessary in order to ensure that slave states did not have an unfair economic advantage. ​