What is the reason that the author begins with this sentence

An author’s purpose is his reason for or intent in writing.

An author’s purpose may be to amuse the reader, to persuade the reader, to

inform the reader, or to satirize a condition.

An author writes with one of four general purposes in mind:

1. To relate a story or to recount events, an author uses narrative

writing.

2. To tell what something looks like, sounds like, or feels like, the

author uses descriptive writing

3. To convince a reader to believe an idea or to take a course of

action, the author uses persuasive writing.

4. To inform or teach the reader, the author uses expository writing.

Explanation:

An author’s purpose is reflected in the way he writes about a topic. For

instance, if his purpose is to amuse, he will use jokes or anecdotes in his

writing.

Clues to an author’s purpose may be found in titles, prefaces, and the author’s

background.

is this multiple choice?