How did Gutenberg change the original concept of the printing press?

Responses
A Gutenberg was the first to create the concept of the printing press.Gutenberg was the first to create the concept of the printing press.
B Gutenberg mechanized the printing press making mass-production possible.Gutenberg mechanized the printing press making mass-production possible.
C Gutenberg invented movable type allowing books to be mass-produced very cheaply.Gutenberg invented movable type allowing books to be mass-produced very cheaply.
D Gutenberg added color to the printing press, previously all copies had been black and white.Gutenberg added color to the printing press, previously all copies had been black and white.

B Gutenberg mechanized the printing press making mass-production possible.