Question

before johannes gutenberg invented the printing press in the fifteenth century, books had to be written out and copied by hand. this labor - intensive process made books rare and expensive. the printing press changed that by using movable type, pieces of metal with raised letters. individual characters could be reused to print multiple copies of one page. then, the characters could be rearranged to print copies of a different page. this enabled the mass production of books, broadening the reach of literature and ideas to a wider audience. as books became increasingly available, more and more people learned how to read, spurring the cultural and intellectual growth of society. gutenbergs invention marked a turning point in the history of communication. what is the main, or central, idea of the passage? the gutenberg printing press transformed the spread of knowledge by allowing for the large - scale production of books. the gutenberg printing press was a convenient technology that involved arranging individual letters of movable type into words. the gutenberg printing press began the mass production of books, which made individual copies less unique and meaningful. the gutenberg printing press was a very costly piece of equipment that few people could afford, which made books rare and expensive.

Explanation:

The passage first mentions the labor - intensive process of hand - writing books before Gutenberg's printing press. Then it focuses on how the printing press with movable type enabled mass production of books. This mass production led to books being more available, more people learning to read, and cultural/intellectual growth. The key is that the printing press's ability for large - scale book production transformed knowledge spread.
The second option only describes a part of the printing press's mechanism (arranging letters), not the overall impact. The third option's claim that mass production made books "less unique and meaningful" is not supported by the passage. The fourth option is incorrect as the printing press made books less rare and expensive (the opposite of what it says).

Answer:

The Gutenberg printing press transformed the spread of knowledge by allowing for the large - scale production of books.