Can anyone explain which two factors combine to form an author's purpose? I'm stuck on my homework.

[Goben]

I'm in 8th grade and we're learning about author's purpose in English class. I thought I understood it—like to persuade, inform, or entertain. But then my teacher asked this specific question: which two factors combine to form an author's purpose for writing a text? and I completely blanked. I've been searching online and getting conflicting answers. Some sources say audience and message , others say purpose and audience , and I've even seen subject and occasion mentioned . My textbook isn't clear either. For those who've taken this class before, what's the actual answer? Is it always the same two factors, or does it depend on the text? I have a test tomorrow and I'm panicking. Any help would be amazing.