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

Ex Input:
Who is the only British Prime Minister to serve under 3 monarchs?

Ex Output:
prime minister of the united kingdom


Ex Input:
Who hosted Call My Bluff?

Ex Output:
call my bluff


Ex Input:
Who played Billy the Kid in the film The Left Handed Gun?

Ex Output:

billy the kid