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

Q: What are Proxima Centauri, Sirius A, Pollux, Arcturus and Betelgeuse?

A: arcturus
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Q: Who has taken over the TV role of Doctor Who, from actor David Tennant?

A: doctor who
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Q: What style of facial hair was famously worn by American Civil War general Ambrose Burnside?

A:
ambrose burnside
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