Which of the Following Allowed the Ottoman Turks to Triumph

Which of the following allowed the Ottoman Turks to triumph over other warrior bands in Anatolia?

A) They welcomed those with different religious beliefs.
B) They rejected Islamic religious authority, which forbade warfare against fellow Muslims.
C) They had no geographic base to defend, thus freeing them to remain constantly on the attack.
D) They adopted Shiism from the Safavids, thus neutralizing a major threat on their borders.