A. he encouraged Catholics to question a number of practices
of the church including the sale of indulgences.
Explanation:
Martin Luther is the father of Protestant Reformation. He was a Catholic priest and a seminar theologian in Wittenberg, Germany. In the 1510s, he went to Rome and came back shocked by the sale of indulgences and papal bulls for the forgiveness of sins. He couldn´t agree with those acts aimed at enlarging the chests of the Church. After a long reflection, he openly questioned them and the authority of the Vatican. He said that Christians could win God´s grace by faith only, not through buying indulgences, and that the Bible was the ultimate authority in religious matters. The furious reaction of the Vatican was to excommunicate him given his refusal to retract.
