During the sixteenth and seventeenth centuries, Africa played a significant role in the global economy, particularly through its involvement in the transatlantic slave trade and the exchange of key commodities. The most accurate statement reflecting Africa's role during this period is:
a. Africa sold gold, ivory, and enslaved people while under the control of Portugal.
During this era, regions in Africa, particularly West Africa, were heavily involved in the trade of gold and ivory, which were highly sought after in Europe and beyond. Furthermore, the slave trade grew significantly during this period, with many African states participating in the capture and sale of enslaved individuals to European traders, particularly those aligned with Portuguese interests.
While the other statements contain elements of truth regarding Africa's various trade activities, they do not comprehensively capture the overarching dynamics of the era as statement (a) does.