Question #N694

The invention of the printing press in the 15th century revolutionized the way information was disseminated. Before, books were painstakingly copied by hand, making them expensive and rare. But with the printing press, books could be reproduced quickly and cheaply, making them more accessible to a wider audience. Printing also played a key role in the spread of literacy.

Which choice best corrects the error in the underlined portion?
A. books were painstakingly copied by hand, making it expensive and rare.
B. books were painstakingly copied by hand, making they expensive and rare.
C. books were painstakingly copied by hand, making them expensive and rare,
D. books were painstakingly copied by hand, making it expensive and rare;