TASK DEFINITION: Given a factoid/trivia type question, generate the topic of the question. The topic is the entity the question talks about.
PROBLEM: What is the capital of the U.S. state of Connecticut?

SOLUTION: connecticut

PROBLEM: Which English town shares its name with the state capital of Delaware?

SOLUTION: delaware

PROBLEM: Which great river flows though China, Laos, Cambodia and Vietnam to the South China Sea?

SOLUTION:
china