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

Ex Input:
Which of these was the title of Bobby Darin's first million selling single?

Ex Output:
bobby darin


Ex Input:
July 1938 saw the first ascent of the North Face of which Alpine mountain?

Ex Output:
alps


Ex Input:
The film `Bicentennial Man` starring Robin Williams was based on a story by which author?

Ex Output:

bicentennial man