Question: Which Californian county is the home of a Ska band that Charles Grey wrote songs for?
Sentence (from "Charles Gray (musician)"): Charles Gray is an American musician, best known for his tenure as the guitarist for the Orange County rock band The Aquabats, of which he served as a member from 1994 to 2000 under the stage name of Ultra Kyu and later The Mysterious Kyu (pronounced as the letter Q).
Relevant evidence: No