"Lucrative cash crops" is the best option from the list, but it should be noted that conditions for the workers, who were almost all slaves, were quite bad and dangerous.
The British had more weapons and supplies. They also had better resources and more people fighting on their side during the war.
Answer: the Kushi te Empire
Slavery was especially common in the colony of South Carolina because South Carolina was heavily agrarian, and its economy relied almost exclusively on the growth of crops, which required a large amount of slave labor.
