Final answer:
The East-West Schism was politically caused by a dispute over papal authority, with the Western Church asserting the Pope's supremacy and the Eastern Church favoring a more equal structure among patriarchs.
Step-by-step explanation:
The political cause of the East-West Schism was B) Dispute over papal authority. This disagreement stemmed from the Western Roman Church's insistence that the Pope held supreme authority over all matters of the church, while the Eastern Orthodox Church believed that the patriarchs had equal authority. The central issue was whether the Pope in Rome should have jurisdiction over the entire Christian Church or if he was simply 'first among equals' among all the patriarchs. This dispute was exacerbated by linguistic and cultural differences, as well as doctrinal variations, but the crux of the political divide was the question of papal supremacy.