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

Example Input: Which 1970s musical film starred Angela Lansbury as a trainee witch?
Example Output: angela lansbury

Example Input: Chelsea won the 2009 FA Cup final 2-1.  Who were the beaten finalists?
Example Output: 2009 fa cup final

Example Input: What was discovered in the American River in California in 1848 by carpenter and sawmill operator James W Marshall?
Example Output:
california