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

Q: The counties of Alameda, El Dorado, Fresno, Marin, Mariposa, Nevada, Orange, Riverside, Sacramento, San Bernardino, San Joaquin, San Mateo, Santa Clara, Santa Cruz, Sonoma and Ventura are in what state of the USA?

A: santa clara, california
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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: Which (liquid) foodstuff has the chemical formula CH3COOH?

A:
acetic acid
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