Why did African merchants and rulers participated in the slave trade

Why did African merchants and rulers participated in the slave trade?

Because Instead, European traders generally relied on a network of African rulers and traders to capture and bring enslaved Africans from various coastal and interior regions to slave castles on the West and Central African coast. Many of these traders acquired captives as a result of military and political conflict, but some also pursued slave trading for profit.

which statement best describes the relationship between the fourteenth amendment and the african american civil rights movement?