I’m guessing if “know” and “no” are italicized:
homonyms
Explanation:
Antonyms are words that are the opposite, for example UP and DOWN. Synonyms are words that mean the same thing, like “mad” and “angry.” Homonyms are words that are spelled the same, or which SOUND the same, but which have different meanings.
Looking at this sentence, you can hear that “know” and “no” SOUND the same, but mean different things. Therefore, they are homonyms.
