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

[Q]: Barabas is the central character in what 16th century play?
[A]: barabas


[Q]: Princess Estelle, Duchess of Ostergotland, granddaughter to King Carl XVI Gustaf, became 2nd in line to what nation's throne when born in 2012?
[A]: carl xvi gustaf of sweden


[Q]: What bebopping saxophonist was known as Bird?
[A]:
bird