Why was Ivan III called "the Great"? A. He unified Russia, took the title of tsar, and rebuilt Moscow's Kremlin. B. He expanded
the Russian Empire, freed the serfs, and wrote a new code of law. C. He went to war against the Tatars, rebuilt the city of Kiev, and married a Greek tsarina. D. He defeated the Mongols, introduced a new religion to Russia, and built a magnificent cathedral
