Farming/ slavery.
This answer really depends on what the question is asking, the southern economy banked heavily off of farming, BUT it was impossible to provide and have such an abundance of crops without slavery. So, it depends on the options you have.
Hope this helps, man!
The answer is D have a good day
Answer: B ) The arms race
Explanation: The nuclear arms race was an arms race competition for supremacy in nuclear warfare between the United States, the Soviet Union, and their respective allies during the Cold War. During this very period, in addition to the American and Soviet nuclear stockpiles, other countries developed nuclear weapons, though none engaged in warhead production on nearly the same scale as the two superpowers.
Peter the great is the answer hope this helps have a great day!