Here are some possible interpretations, depending on the context:
* "De quoi": This is the most likely option, meaning "what" or "what about". It is used in questions, like "De quoi parles-tu?" (What are you talking about?)
* "De quelle": This means "of which" or "what" and is used when referring to a specific thing. For example, "De quelle couleur est la robe?" (What color is the dress?)
* "De qu'": This is a contraction of "De que" and is sometimes used, though less common than "De quoi". It still means "what".
If you provide more context about where you saw "de q," I can give you a more accurate interpretation.