Given a factoid/trivia type question, generate the topic of the question. The topic is the entity the question talks about.

Ex Input:
Which BBC current affairs programme, the longest-running in the world, is 60 years old this year ?

Ex Output:
bbc


Ex Input:
Established in 1919, which is the world's oldest surviving airline?

Ex Output:
airline


Ex Input:
Who carried the flag for Britain at the opening ceremony at the 2012 Olympic Games?

Ex Output:

britain