GETTIN REAL TIRED OF YOU, GARLIC
"What is it, garlic?" does not really make clear sense in written English with no context. Is the meaning really "What is it? Garlic?"
Could "What is garlic?" have been a correct answer? If not how would you write "What is garlic?" in Italian?
What is garlic was also my first answer. What is it, garlic? does not sound very natural to me; I would rather say:
What does garlic mean?
Garlic, what is that?
What is garlic?
Yeah, a comma doesn't seem strong enough in this case. This seems like the duty of a colon or maybe a semicolon. Just a weird sentence in general.
"Nothing, onion, I'm just a little nervous knowing I'll be cut for a soup any time soon ..." :P
I read it also as "What is it, garlic?" as in "What's troubling you?"
The hover-hint for Cos' says Cos'.