Which of the following was a short-term effect of the creation of the Mongol states shown in the map?

a. Rapid urbanization into centers of Mongol culture
b. An increase in the volume of long-distance commerce due to Mongol protection provided for trade routes
c. Population growth due to Mongol rejection of traditional monogamous marriages
d. A decline in the number of people practicing Islam as people converted to Mongol polytheism for political favors