Why did the trans-atlantic slave trade expand after the 16th century?

The Atlantic slave trade, also known as the transatlantic slave trade, refers to the slave trade that took place across the Atlantic Ocean between the 16th and 19th centuries. The vast majority of the slaves involved in the Atlantic traffic were Africans from the central and western parts of the continent, mostly prisoners of the wars between rival ethnic groups that were sold by African slave traders to European buyers, who transported them to their colonies in North and South America. There, the slaves were forced to work in the plantations of coffee, coconut, tobacco and cotton, in the gold and silver mines, in the rice fields, in the construction industry, in the wood, in the construction of boats and in homes as servants.

The European colonialists initially practiced a system at the same time of forced labor and slavery of Native Americans, enslaving most of the natives of the New World. For different reasons, Africans replaced Native Americans as the main enslaved population of America. In some cases, such as that of the Caribbean islands, wars and diseases such as smallpox eliminated the natives completely. In other cases, such as in South Carolina, Virginia and New England, the need for alliances with native tribes coupled with the availability of African slaves at affordable prices led to the progressive demise of Native American slavery.

the correct answer is c.