Final answer:
Pope Urban II called for the First Crusade A) to elevate the pope's power by uniting Christians and to protect the lands of the Byzantine empire.
Step-by-step explanation:
Pope Urban II called for the First Crusade in order to A) elevate the pope's power by uniting Christians.
He presented the idea of a religious war at a council in Clermont, France, in 1095, in response to the Byzantine request for aid.
Urban's goal was to free the Christian Holy Land from non-Christian rulers, particularly the Turks, to protect the Christians living there.