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

Ex Input:
Which analgesic drug, first isolated in 1804, was named after the Greek god of dreams ?

Ex Output:
analgesic

Ex Input:
Which jockey won the 1981 UK Grand National on Aldaniti?

Ex Output:
aldaniti

Ex Input:
The headquarters building of which government agency is known as 'The Doughnut' due to its shape?

Ex Output:
the doughnut