How did the beliefs of the roman catholics differ from the eastern orthodox form of christianity?

Charlemagne's crowning made the Byzantine Emperor redundant, and relations between the East and the West deteriorated until a formal split occurred in 1054. The Eastern Church became the Greek Orthodox Church by severing all ties with Rome and the Roman Catholic Church — from the pope to the Holy Roman Emperor on down.

i believe the correct answer is option b. most eastern european nations joined nato.

though i could be wrong, option d. the eastern european nations were granted complete independence, would be another choice.

hope this ! : )