Which topic sentence indicates that a certain text contains information on the formation of the Confederacy before the Civil War?

Thousands of Africans were brought to America as slaves during the colonial era.

A large number of whites in the Southern slave states did not want to be treated as second-class citizens.

Although a majority of Southerners did not have slaves, they supported slavery as a part of the social and economic order.

There were many misunderstandings between Northern states and Southern states because of the elections.