To what extent did Islam successfully penetrate the populations of east Africa?
a. Most clans and the most important lineage groups outside of the east African cities were converted to Islam in order to participate in trade.
b. Few literate people converted to Islam but the vast majority of herders converted rapidly.
c. Islam penetrated very little into the interior among the hunters, pastoralists, and farmers, and even the areas near the trading towns remained relatively unaffected.
d. Islam spread from the cities to the hinterland in such a way that eventually the countryside was more Islamic than were the cities.
e. As in Asia, the conversion of the coastal cities led to almost complete conversion of the populations lying inland.
Answer: C