In Early American, the Importation of African Slave Labor Was

In early American, the importation of African slave labor was attractive because:

A) American Indians were difficult to subdue and were a potential major threat because they were familiar with the countryside and could put up fierce resistance
B) large-scale, prolonged use of indentured White servants was unrealistic because they were freed after a period of servitude
C) The enslavement of Africans created a large labor pool of workers who did not know the land, and it helped to elevate all Whites to a higher status
D) All of the above