Which was a major source of conflict between the Ottoman and Safavid empires? A. Each empire wanted to control the trade between the Muslim world, Africa, and East Asia. B. The two empires competed for territory in western Europe. C. The Ottomans and Safavids often went to war with each other over issues of leadership. D. Most inhabitants of one empire were Shi'a Muslims and most in the other empire belonged to the Sunni branch of Islam.