In which sentence does the introductory word to the noun clause function as an adverb?

Whatever my supervisor advised, I did.

I do not know when the flagpole was painted.

The historian said that the flag was 200 years old.

She could not decide which Scandinavian flag was her favorite.

Bot GPT 3.5 Bot GPT 3.5 answered

I do not know when the flagpole was painted.