puzzle creation - Guessing among 3 possibilities with a single question - can this be done with letters as well as numbers?

This is an open question to all.

I have seen a few " I am thinking of a number/s-- can you guess by asking one question to which I can only answer Yes, No or may be" puzzles which are interesting from logic perspective.

Are there similar puzzles that talk about Letters instead of numbers?

If not can one design a hard puzzle ( I am thinking of letters L,M or N just as an example) and have a defined solution?

If this type of puzzle already exists then I am sorry for this question. I could not find it.