The statement that best explains why the author describes Pegasus at the beginning of the story is this:
An exposition is an introduction that is often given at the opening of a text. Most times, the exposition provides a glimpse of the characters in the story.
So since the author described Pegasus at the beginning of the story, we could refer to that as an exposition.
Learn more about exposition here:
https://brainly.com/question/2227698
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