A. They would have more power to vote on behalf of their interests.
Step-by-step explanation:
The North and South both wanted to maximize their representation in Congress because they would have more power to vote on the behalf of their interests.
The main issue that the North and South disagreed on was the issue of slavery. Remember, during this time the South was focused on agriculture, while the North was more focused on industrialization. The South needed people for labor work in order to thrive, so they desperately wanted to keep slavery. On the other hand, the North was not too keen on slavery. While some people didn't really care a whole lot, a lot of people did care in the North and even wanted to abolish slavery.
The South felt that if the North had more representation in Congress, they would try to abolish slavery, which would be bad for the livelihood of the Southern people. The North felt that if the South had more representation in Congress, they would try to expand slavery, which the North did not want.