Given a factoid/trivia type question, generate the topic of the question. The topic is the entity the question talks about.
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Question: Krist Novoselic and Dave Grohl were two thirds of which band, formed in Aberdeen (Washington State) whose albums include Bleach and In Utero?

Answer: dave grohl


Question: Who was the CBS News anchor-man known as 'the man Americans most trust'?

Answer: news presenter


Question: Which pop group of the 60's and 70's released albums entitled `Days of Future Passed' and 'A Question of Balance'?

Answer:
a question of balance