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: What's the name of Doctor Who's home planet ?

Answer: doctor who

Question: Ewart was the middle name of which British Prime Minister?

Answer: prime minister of the united kingdom

Question: Which country on the east coast of the Bay of Bengal is bordered by China, Laos, Thailand, Bangladesh and Nepal?

Answer:
china