What Permitted the Janissaries to Gain a Position of Prominence

What permitted the Janissaries to gain a position of prominence in the Ottoman Empire?

A) Their control of artillery and firearms gave them prominence over the aristocratic Turkish cavalry.
B) Their control of the bureaucracy made them indispensible to the operation of the empire.
C) As members of the royal family, they had access to the sultans.
D) They rapidly gained control of the mosques of the Ottoman Empire and were able to define religious orthodoxy.