TASK DEFINITION: Given a factoid/trivia type question, generate the topic of the question. The topic is the entity the question talks about.
PROBLEM: I which European city will you find 'Dam Square'?

SOLUTION: dam square

PROBLEM: And Then There Were None?

SOLUTION: and then there were none

PROBLEM: Arthur Wynne of Liverpool invented which teaser in 1913?

SOLUTION:
arthur wynne