The Article primarily discusses .Press enter to interact with the item, and press tab button or down arrow until reaching the Submit button once the item is selectedA. the reasons why camel caravans ran trade routes across ancient Africa, including the fact that there were gold mines near the Sahara DesertB. the reasons why camels were put to work traveling trade routes in ancient Africa, including the fact that they close their nostrils to keep out sandC. the ancient empire of Wagadugu, which established a trade monopoly to become the richest empire in the western Sudan regionD. the ancient empire of Wagadugu, which was weakened by invaders and drought and eventually swallowed up by the Mali Empire