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

Example Input: The song Don't Rain On My Parade features in which musical?
Example Output: don't rain on my parade

Example Input: What is the cathedral church of Rome?
Example Output: cathedral

Example Input: In which Agatha Christie novel does Hercule Poirot commit murder?
Example Output:
hercule poirot