How did the Columbian Exchange affect the slave trade? o It encouraged communication about the evils of slavery. It caused Europeans to stop enslaving American Indians. o It allowed people to be enslaved and transported to the Americas. 0 It caused the demand for enslaved laborers to decline.

Its C pretty sure

Explanation:

Because It says that they need a trade system that goes to the Americans and that's how they made the Columbian trade. Also they needed slaves in the Americans so they traded slaves to the Americans.  

d.

the northwest territory became the most densely populated area in the u.s.