Largely because of the dedication of their soldiers and their genius for adapting to new weapons, the ottomans were able to

a. occupy spain and convert the people to a new religion.
b. maintain their empire despite civil war and foreign invasions.
c. conquer and control the territory formerly held by the mongols.
d. rule their empire solely through the use of threats and military force.

personally i think it's c. but i just wanted confirmation