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.

Q: Category: ART 
Clue: Medieval artists gave triangular ones to the trinity, round to the angels & rectangular to living holy people

A: halos
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Q: Category: DIMENSIONS 
Clue: Don't lose the thread--there are 10 or so dimensions in this physics theory

A: string theory
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Q: Category: ACTORS & THEIR ROLES 
Clue: You could say Dan Aykroyd's role as this director in "Chaplin" was the "Keystone" of the film

A:
mack sennett
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