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

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

Example Input: The 2002 Winter Olympics were held in which city?
Example Output: 2002 winter olympics

Example Input: Which jazz musician, he played the tenor sax and clarinet, was nicknamed 'Prez'?
Example Output:
tenor saxophone