Final answer:
The Protestant Reformation was a religious movement in the 16th century sparked by Martin Luther's objections to the Catholic Church's practices, including the sale of indulgences.
Step-by-step explanation:
The Protestant Reformation was a religious movement in the 16th century that was sparked by Martin Luther, a German monk. Luther publicly objected to the sale of indulgences by the Catholic Church, which led to his excommunication. His ideas, focused on faith alone and the authority of scripture, spread throughout Europe with the help of the printing press.