Which event occurred soon before the Great Schism of 1054 and helped cause the event?
А)
Pope Urban II authorized a disastrous expedition to conquer Jerusalem
B)
Pope Clement V moved the seat of the church's power from Rome to Avignon
C) Pope Leo IX and Patriarch Michael Cerularius excommunicated each other,
D)
Pope Leo X ordered the sale of indulgences to fund repairs of St. Peter's Basilica.