Which of the Following Sparked Martin Luther's Challenge to the Catholic

Multiple Choice

Which of the following sparked Martin Luther's challenge to the Catholic Church?

A) Luther believed that true knowledge of God came through meditation.
B) Luther wanted German cathedrals to rival those of Rome in their grandeur.
C) Luther was disgusted with corrupt church practices such as the selling of indulgences.
D) Luther was shocked by what he experienced as an itinerant monk.