You will be given a trivia clue, and the category it belongs to. You should answer with the best answer that belongs in the category and is described by the clue. For simplicity, answers should be in all lower cased letters.

Category: MILITARY TRAINING BASES 
Clue: Service branch with a San Diego recruit depot & a Yuma air station
marines

Category: LITERARY TRILOGIES 
Clue: "Number One" is actually the number two novel in a trilogy by this author of "U.S.A."
john dos passos

Category: PRETZEL LOGIC 
Clue: The pretzel type of this sweet treat holder is a Philadelphia tradition

an ice cream cone