Which fact is true about all words with the root set. A. They relate to breathing. B. They will all have the same meaning. C. They relate to air. D. They all sound the same.

None of the provided options (A, B, C, D) accurately describe a true fact about all words with the root "set." The root "set" can be associated with a variety of meanings and contexts, such as placing something down, a collection of items, or establishing something. So none of the statements are correct regarding all words derived from that root.