Option C. i.e The Western Roman Empire fallowed the Roman Catholic Church, while as the Eastern Roman Empire fallowed the Orthodox Christian Church aptly describes the religious differences between the Western Roman Empire and the Eastern roman Empire also known as Byzantine Empire.
One of the major difference between the two is related to papal primacy. While as Western Roman Empire considered the pope as an infallible, the Eastern Roman Catholic don't consider pope as an infallible and supreme over the other churches.