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: I which European city will you find 'Dam Square'?

Answer: dam square


Question: What is the second largest of the Balearic Islands ?

Answer: balearic islands


Question: The explorer and navigator, Christopher Columbus, was born around 1451, in which city?

Answer:
columbus