TASK DEFINITION: Given a factoid/trivia type question, generate the topic of the question. The topic is the entity the question talks about.
PROBLEM: Which country music star, writer of the song Your Cheatin' Heart, died on New Year's Day 1953?

SOLUTION: country music

PROBLEM: Charon is a moon which orbits which body?

SOLUTION: charon

PROBLEM: Which BBC 2 programme features radio controlled machines fighting each other?

SOLUTION:
bbc