Which best describes the southern economy?
a. cotton was a primary cash crop.
b. increased cotton production caused an increase in slavery.
c. supplied cotton to northern textile industries.
d. all of the above.

Answer - A - Cotton was a primary cash crop

Reasoning - First we have to look at the question (Southern Economy). Which already gives you a hint that yes all the other industrialization and delivery help with money. But not as cotton was a base line for cash crop and its was the foundation to the south. Without cotton being a primary cash crop or white gold. Will equal to no money for the south economy. Yes A is the correct answer.