One important factor in the gradual drifting apart of the Western (Catholic) and Eastern (Orthodox) Churches during the period 600 AD - 1000 AD was the fact that A) Catholic religious festivals were significantly different from Orthodox festivals. B) Muslim pressure led Byzantium to being less aligned with Rome in political matters. C) the emphasis on Latin in the West and on Greek in the East led to a sense of alienation on both sides. D) the Patriarch of Constantinople was often engaged in trying to take control of matters in the West away from the Pope.