"We have also markets. . . . These are sometimes visited by stout mahogany-coloured men from the south west of us. . . . They always carry slaves through our land; but the strictest account is exacted of their manner of procuring them before they are suffered to pass. Sometimes indeed we sold slaves to them, but they were only prisoners of war, or such among us as had been convicted of kidnapping, or adultery, and some other crimes, which we esteemed heinous. -Olaudah Equiano, The Interesting Narrative of the Life of Olaudah Equiano

From this excerpt, written by a West African, what one can be inferred about the practice of slavery among West Africans?

A. Portuguese traders greatly expanded the West African slave trade.
B. West Africans treated enslaved people fairly and kindly.
C. Slavery was not based on race or parentage.
D. Enslaved people were mostly forced to serve as soldiers.