Otto I Used Bishops and Abbots to Administrate His Empire

Otto I used bishops and abbots to administrate his empire because

A) Germany had no concept of "liege lord" and therefore Otto had little authority over vassals.
B) they had no hereditary claims to their fiefs.
C) he had few financial resources and therefore relied on the wealth of the Church and its officials to govern.
D) with little education, Otto could intimidate Church officials with his authority and power.
E) the "Ottonian Renaissance" promoted the Church in the governance of the empire.