Answer: B. Indulgences
Step-by-step explanation:
The sale of indulgences (forgiveness of sins) by church persons was one of the main factors that led to the Reformation. Martin Luther was the first reformer to point to this phenomenon. In that way, the church gained enormous wealth. That was the main but not the only factor that led to the Reformation. Church people generally lived in luxury and wealth, as Luther pointed out, and many other reformers throughout Europe.