The gold-salt trade was an exchange of salt for gold between Mediterranean economies and West African countries during the Middle Ages. West African kingdoms, such as the Soninke empire of Ghana and the empire of Mali that succeeded it, were rich in gold but lacked salt, a commodity that countries around the Mediterranean had in plenty. Salt was important for replacing fluids and preserving food in the tropical climate south of the Sahara.Therefore, the answer to this question is A) Ghana was the primary source of gold.
