Answer: a. Martin Luther
Step-by-step explanation:
Martin Luther is a German monarch who opposed the arbitrariness and luxury of church faces. Martin Luther left his theses at Wittenberg Cathedral, pointing to the negative phenomena in the church. In the first place, Luther opposed the sale of forgiveness for sins by churchmen. His religious reformation profoundly affected political, economic, educational, and linguistic circumstances in the world, making him one of the most influential figures in European history.