Given a factoid/trivia type question, generate the topic of the question. The topic is the entity the question talks about.

Example Input: Mr Barkis, Edward Murdstone and Tommy Traddles are all characters in which Charles Dickens novel?
Example Output: charles dickens

Example Input: Who had a hit album in 2010 with Can't Be Tamed?
Example Output: can't be tamed

Example Input: The film 'Murder, She Said' is based on which Agatha Christie book in which 'Miss Marple' witnesses a passenger on a train being strangled?
Example Output:
murder, she said