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

[Q]: The film The Curious Case of Benjamin Button, starring Brad Pitt, is based on a short story by whom?
[A]: the curious case of benjamin button

[Q]: Who did boxer Floyd Patterson defeat to regain the Heavyweight Championship in June 1960?
[A]: boxing

[Q]: What links the US, 2 May 2011 and Abottabad in Pakistan?
[A]:
abbottabad