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

Ex Input:
Of all the actors who played Doctor Who in the TV series of the same name, who appeared in the most episodes?

Ex Output:
doctor who


Ex Input:
In which country was actor Basil Rathbone born?

Ex Output:
basil rathbone


Ex Input:
Acute Coryza is a medical term for which common complaint?

Ex Output:

rhinitis