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: Which alliteratively-named politician served as Abraham Lincoln's Vice-President between 1861 and 1865?

Answer: abraham lincoln


Question: On which Beatles album does the song Dr Robert appear?

Answer:
the beatles