Answer:
Option D is the correct answer.
Step-by-step explanation:
Charlemagne, also known as Charles The Great, and name Charles I, was a governor named King of the Franks in 768, King of the Lombards from 774, and Emperor of the Romans from 880. He contributed to unite the vast majority of Europe during the Middle Ages. He held a close relationship with Pope Leo III and with the church in general. Due to this, he forced all of the people he conquered to convert to Christianity.