Given a factoid/trivia type question, generate the topic of the question. The topic is the entity the question talks about.

Q: Charon is a moon which orbits which body?

A: charon
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Q: What was the last silent film in which Chaplin's little tramp appeared?

A: chaplin
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Q: Today marks the 90th anniversary of the birth of Art Clokey, a pioneer in the field of stop motion clay animation, who is best remembered for what green shapeshifter?

A:
art clokey
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