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

Q: Feb 15, 1564 saw the birth of what famed Italian physicist, mathematician, astronomer, and philosopher, who discovered the first 4 moons of Jupiter?

A: astronomer
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Q: Which BBC current affairs programme, the longest-running in the world, is 60 years old this year ?

A: bbc
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Q: A clavichord is what type of instrument?

A:
clavichord
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