The correct answer is a the prohibition of alcohol
It didn't stick however, and now, the 18th amendment is not in use anymore and alcohol is legal.
Answer:
During the crusade, Frederick I, Holy Roman Emperor, had almost besieged Constantinople because of the failure of the Byzantines to provide him with safe passage across the Dardanelles. The Byzantines for their part suspected him of conspiring with the breakaway Byzantine provinces of Serbia and Bulgaria.
Explanation:
The correct answer among all the other choices is C. The feuds between religious and secular power over investiture. The fall of the western Roman empire contributed most directly to this circumstance. Thank you for posting your question. I hope that this answer helped you. Let me know if you need more help.