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

Feb 15, 1564 saw the birth of what famed Italian physicist, mathematician, astronomer, and philosopher, who discovered the first 4 moons of Jupiter?
astronomer

In which range of mountains are the two highest peaks Aconcagua and Ojos Del Salado?
aconcagua

In which Shakespeare play does Caliban appear?

caliban