Answer:
Option: A) Islam would have spread into Europe.
Step-by-step explanation:
The Battle of Tours fought between Franks and Burgundian against the Muslims (Umayyad Caliphate) in 732. The leader of the battle from the Christian side was Charles Martel. He played a significant role in defeating the army of Spanish Moors who were trying to enter into Western Europe. If the Franks were unable to win the battle, then Islam would have replaced Christianity in Europe. Europe developed under Muslim rule would have completely change European history. Christianity remained in Europe with ending Muslim conquests towards Europe.