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

Example Input: What is the SI unit of capacitance?
Example Output: capacitance

Example Input: What horse won the 2009 Grand National?
Example Output: 2009 grand national

Example Input: Anwar Sadat was President of which country when he died in 1981?
Example Output:
anwar sadat