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

Example Input: Which two brothers had hits with Cathy's Clown and Wake Up Little Susie?
Example Output: cathy's clown

Example Input: What currency is used on Christmas Island?
Example Output: christmas island

Example Input: Competitors from which country won the most medals at the World Artistic Gymnastics Championships held in Rotterdam, Netherlands from 16 to 24 October 2010?
Example Output:
artistic gymnastics