The answer is C. Because William Jennings Bryan who was heavily supported by populist during the election of 1896 said something about this during his "Cross of gold speech".
The Atlantic slave trade was so harmful to African nations because Africa missed out on generations of economic, cultural, and political development.
B. Africas economies crashed because of their lack of natural resources
If this was multiple choice I'd say the answer is (B)
But I'm a little confused the wording is a little whack.