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

[EX Q]: Who played boxer James Braddock in the 2005 biopic Cinderella Man?
[EX A]: james j. braddock

[EX Q]: Who composed Air on the G String?
[EX A]: air on the g string

[EX Q]: What is Edward Hopper's famous night-time painting of customers in an American diner?
[EX A]:
edward hopper