Answer:
D
Step-by-step explanation:
The Slavery was growing more unpopular in the north states as people started to ask themselves the question "If we fought for freedom is it really right for us to have enslaved people?" While the North was prospering with the new industry ideas the South relied heavily on plantations which which in turn relied on slaves to be running. In the disagreement some states even threatened to leave the union if slavery was outlawed.