How can you answer without a noun?

Sh. Don't ask, don't tell.

You may use a pronoun in place of a noun.

Possible, but rarely done. Pronouns can be used, of course, but sometimes not even that. Try talking without addressing. Shout; Yes! and No!

Slowly

Simple!

Surely..mostly...possibly?

Yes, I can answer it. By using a pronoun.

talking and writing, I never use my noun.

By being very careful

Depends on the question.

But in your case my answer would be:

I acknowledge you.

Cautiously...