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: Which biologist was known as Darwin's Bulldog?

Answer: charles darwin


Question: Field Marshal Arthur Wellesley, shares his better known title with which Southern Hemisphere capital city?

Answer: arthur wellesley, 1st duke of wellington


Question: The Churn, the Windrush, the Cherwell and the Mole are all tributaries of which major river?

Answer:
river windrush