What Strategy Did the Church Use That Allowed It to Steadily

What strategy did the church use that allowed it to steadily gain power over secular monarchs?

A) It consistently claimed more power in theory than it had in practice,and therefore they always gained through compromises.
B) It used the threat of excommunication to force unruly monarchs into yielding to the church.
C) It encouraged monarchs to give land to the church on the grounds that clergy would be more loyal than ambitious lords.
D) It encouraged them to engage in costly crusades,which weakened their financial resources and manpower.
E) It agreed to make candidates for church offices give an oath of homage to kings in return for a generous fee.