TASK DEFINITION: Given a factoid/trivia type question, generate the topic of the question. The topic is the entity the question talks about.
PROBLEM: The site of the 1461 Battle of Mortimer's Cross lies in which English county?

SOLUTION: battle of mortimer's cross

PROBLEM: Who has written a series of novels, entitled The Dark Tower, of which the first, in 1982, was entitled, The Gunslinger?

SOLUTION: the dark tower

PROBLEM: Who was the admiral of the French fleet defeated by Nelson at the Battle of Trafalgar?

SOLUTION:
battle of trafalgar