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

Q: What was the name of Chuck Berry's 1972 hit which gave him his first number one?

A: chuck berry
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Q: What name is given to the disease whereby parasites can change the behaviour of rats and mice, making them drawn to rather than fearful of the scent of cats?

A: cat
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Q: Which English poet's works include 'Birthday Letters?

A:
birthday letters
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