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

Example Input: The bells were ringing for Chuck Berry when this song made it to No1. His first and only British No. 1. What song?
Example Output: chuck berry

Example Input: Who composed 'Eine Kleine Nachtmusik' in the 18th Century?
Example Output: eine kleine nachtmusik

Example Input: With which pop duo would you associate Theresa Bazaar and David Van Day?
Example Output:
pop music