Which of the following best explains a development in the trans-­Saharan trade networks in the period 1200–1450? (A) The networks became more dangerous because of religious conflict between Christian and Muslim
states.
(B) The geographic range of the networks increased because of improved commercial practices.
(C) The networks were increasingly disrupted because of the growing importance of maritime commerce.
(D) The value of merchandise along the networks increased because of demand for silver and bronze from
Muslim states in North Africa and the Middle East.