Answer:
Your answer should be B: mercantilism
Explanation:
According to the theory of mercantilism, a nation could increase its wealth and power in two ways. First, it could obtain as much gold and silver as possible. Second, it could establish a favorable balance of trade, in which it sold more goods than it bought. Hope this helped :)
Support troops with paying for supplies
The south didn't grow crops very much, instead they grew cotton which made them rely on the North for crops and other materials. So the correct answer would be "B" since that seems like the most plausible answer.