Answer:
The correct answer is D) He was successful in building a new political center in the East, unified by the Christian religion.
Step-by-step explanation:
This new political center was named "Constantinople" after him. Later, due to the separation of the Roman Empire, it would be part of the East Roman Empire and later on Byzantium. Also, during the reign of Constantine, Christianism started to become the dominant religion in the Roamn Empire.