C. They were promised absolution of their sins if they agreed to fight in the Crusades.
Explanation:
Hoping to mobilize as many Christian fighters for the sacrosanct cause of retaking the Holy Land and Jerusalem from the hands of Muslim "infidels," the Vatican promised absolution of sins to anybody taking part in the Crusade. Anybody who would die fighting the Muslims would go to heaven, according to the church. However, many feudal knights and nobles enriched themselves during the Crusades and took lands and gained privileges in the Middle East.
