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 Brooklyn Bridge crosses which river?

SOLUTION: brooklyn bridge

PROBLEM: On which holiday island are the peaks of 'Ruivo' and 'Arieiro', and the airport of 'Santa Cruz'?

SOLUTION: pico do arieiro

PROBLEM: Who became British Prime Minister in June 1970?

SOLUTION:
prime minister of the united kingdom