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

Example Input: What style of facial hair was famously worn by American Civil War general Ambrose Burnside?
Example Output: ambrose burnside

Example Input: The Battle of Antietam was fought during which war?
Example Output: battle of antietam

Example Input: Who starred in Mogambo, Dial M For Murder, Rear Window and High Society before giving up her film career for marriage in 1956?
Example Output:
high society