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

Q: In which Shakespeare play do the characters Ajax, Achilles and Ulysses appear?

A: achilles
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Q: Chris Martin is the lead singer with which band who had several hits in the 2000s?

A: chris martin
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Q: Which UK actress gave an acclaimed performance as a ballet teacher in the film Billy Elliott?

A:
billy elliot
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