The Ottomans Were Successful in Their Conquests,at Least in Part,because

Multiple Choice

The Ottomans were successful in their conquests,at least in part,because:

A) they brought new ways of fighting to Europe with their introduction of stirrups for their horses.
B) they enlisted the services of Anatolian mercenaries.
C) they had begun as mercenaries of the Ottomans and had established control of Greece,Bulgaria,and the Balkans by the 1390s.
D) their caliph married into the Byzantine royal family and thus had Byzantine support.
E) they promised full citizenship and a job to everyone who surrendered to them.