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: Who painted The Card Players, at Feb 2012 the most expensive artwork in the world?

Answer: the card players


Question: Which biologist was known as Darwin's Bulldog?

Answer: charles darwin


Question: 'All American Prophet', 'Baptize Me' and 'l am Africa' are songs from which musical, currently playing at the Prince of Wales theatre?

Answer:
the book of mormon