Europeans started to enslave Africans.
They started to use slaves instead of indentured servants, because the investment was better. Indentured servants only served for a few years, and then were granted freedom, while slaves were purchased and used for their entire lives. The investment of a slave was better than an indentured servant.
The three most prominent factors that contribute to Africa's lack of economic and human development are corrupt governments, a lack of material resources, and tribal warfare. All of these are somewhat intertwined. <span />
The answer will most likely be c
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