All of the following are true concerning the african slave trade except
(a) portuguese slavers carried slaves to atlantic islands.
(b) in sub-saharan africa, wealth was determined by control of human labor rather than by private property.
(c) most slaves exported from africa came from central africa.
(d) some slaves were transported across the sahara to the mediterranean basin.
(e) muslim merchants had slave suppliers who assisted them in the indian ocean slave trade.