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

Ex Input:
Which analgesic drug, first isolated in 1804, was named after the Greek god of dreams ?

Ex Output:
analgesic


Ex Input:
In which famous film did Michael Caine play a character named Charlie Croker?

Ex Output:
charlie croker


Ex Input:
Which American horse race is run at Churchill Downs?

Ex Output:

churchill downs