Before the split in 1054, the leaders of the eastern church and the western church were a-the patriarch and the pope. b-justinian i and the pope. c-the pope and theodora. d-the patriarch and theodora.

Before the split in 1054, the leaders of the eastern church and the western church were the patriarch and the pope. Option A is correct.

Nowadays, the highest-ranking bishops in Eastern Orthodoxy, Oriental Orthodoxy, the Catholic Church (above major archbishop and primate), and the Church of the East are known as patriarchs.

Schism of 1054, also refered to as East-West Schism, was event that precipitated the final split between the Eastern Christian churches (led by the patriarch of Constantinople, Michael Cerularius) and the Western church (led by Pope Leo IX).

c.) biotic: snails; abiotic: temperature climate