The correct answer to this open question is the following.
Although there are no options attached we can say the following.
Slavery continued to spread after the Revolutionary War because southern landlords needed slaves to continue the production of crops. These slaves worked for long hours in the southern plantations under risky conditions. Indeed, the southern economy depended so much on slaves.
The drafting of the Constitution reflected a growing divide between Northern and Southern states on the question of slavery in that slaves were considered or be counted as three-fifths of a person.
Although framers such as George Washington and Thomas Jefferson -who, by the way, owned slaves- opposed the institution of slavery, delegates during the Constitutional Convention of 1787 in Philadelphia Pennsylvania agreed on establishing a limit to allow slavery in the United States until 1808. This created more tense moments and divided the nation.