23 Although books were eventually printed on a variety of topics, the first books produced on Gutenberg's printing press were primarily on which subject? Travel Medicine Religion Architecture

## Step 1<br />The question is asking about the primary subject of the first books produced on Gutenberg's printing press. Gutenberg's printing press, invented in the 15th century, was a significant innovation in the history of printing and publishing. <br />## Step 2<br />The first books produced on this press were primarily religious texts. This is because the printing press was initially used to produce the Bible, which was a religious text. <br />## Step 3<br />The Gutenberg Bible, also known as the B42, is one of the most famous examples of the books produced on Gutenberg's printing press. This further supports the fact that the primary subject of the first books produced on this press was religion.