Why do authors vary sentence structure in their writing?

Question

Responses

To make their writing fictional.
To make their writing fictional.

To make their writing simpler.
To make their writing simpler.

To make their writing biographical.
To make their writing biographical.

To make their writing more interesting.

Answer 1

To create rhythm and flow, engage the reader's attention, emphasize certain points, and to prevent the writing from becoming monotonous.

Answer 2

just pick one

Answer 3

To make their writing more interesting.