Context: My friend had just finished her exam.
I asked: "How did you do?"
She replied: "Good."
Then we got into a debate whether "good" or "well" was the correct response.
She believes "good" because its slang/informal and becomes an article when standing alone in a single word sentence.
I argued it's an adjective not appropriate in this context, whereas "well" is an adverb so it can be used alone. Also, answering "good" on its own is more colloquialism than slang.
Thoughts?