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

Example Input: Ashgabat is the capital of which country, a former Soviet republic in Asia?
Example Output: ashgabat

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

Example Input: Which animated Disney movie is based on a book by Edgar Rice Burroughs?
Example Output:
edgar rice burroughs