Revise the following sentences to correct each ambiguous, general, weak, or indefinite pronoun reference.

EXAMPLE:
- I enjoy reading science fiction; the one 1 am reading now, Contact, was written by Carl Sagan.
- I enjoy reading science fiction; the novel I am reading now, Contact, was written by Carl Sagan.
- I enjoy reading science fiction novels such as the one I am reading now, Contact. It was written by Carl Sagan.

a. As a boy, Sagan discovered the genre of science fiction, and he read them regularly.