The Five Centers of Christianity

Can you guess what the five centers of Christianity were after Jerusalem fell during the Middle Ages 600-900 AD?
1.Rome
2.Constantinople
3.North Africa
4.Persia (http://en.wikipedia.org/wiki/Assyrian_Church_of_the_East)
5.China search Christianity (http://en.wikipedia.org/wiki/Tang_Dynasty) and A History of Christianity in Asia: Beginnings to 1500 Samuel Moffat