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

Ex Input:
Which film was based on the story The Sentinel by Arthur C Clarke?

Ex Output:
arthur c. clarke


Ex Input:
According to the bible, Zaccariah was the father of which New Testament figure?

Ex Output:
bible


Ex Input:
In which city was David Hockney born?

Ex Output:

david hockney