TASK DEFINITION: Given a factoid/trivia type question, generate the topic of the question. The topic is the entity the question talks about.
PROBLEM: Cinder Cone, composite, and shield are all types of what?

SOLUTION: cinder cone

PROBLEM: Who was the first person to sign the American Declaration of Independence?

SOLUTION: united states declaration of independence

PROBLEM: What is the most populated city in America?

SOLUTION:
united states