How was the Protestant Reformation related to the Gutenberg printing press?
The connection between these two is that the printing press helped to cause the Protestant Reformation.
The ideas of the Protestant Reformation were spread in large part through the printed word. Martin Luther's ideas were printed and were disseminated across Europe. If Luther had had his ideas before the printing press, it would have been much more difficult to expose a large number of people to them. If it had not been possible to print his pamphlets easily, it is possible that the Reformation would not have happened at all or that it would not have spread as quickly or as widely as it did.