Answer: A. He was able to assert his power over two monarchs as well as put down heretical groups.
Step-by-step explanation:
Innocent III was one of the most powerful Popes to live and he expanded the church's power when he asserted his will over that of multiple monarchs including King John of England and King Phillip II of France.
In King John's instance, Innocent III overruled the King's choice for the Archbishop of Canterbury and excommunicated him when he protested until he submitted.
In King Phillip's instance, he annulled his marriage to Agnes of Merania because he said that Phillip was still married to his first wife, Ingeborg of Denmark and again excommunicated him until the King submitted.