Constantine Formally Transferred His Government to the East, to the New

Constantine formally transferred his government to the East, to the new city of Byzantium (Constantinople) , because

A) he thought the government should be centered in the world's largest city.
B) the cultured Greeks were the dominant force there.
C) he feared the encroachment of the Germans.
D) the Germans were advancing from the west and he wanted the capital to be in a safe place.
E) the eastern half of the empire needed protection, and the new capital city had a good strategic position.