Given a factoid/trivia type question, generate the topic of the question. The topic is the entity the question talks about.
--------
Question: Which of these was the title of Bobby Darin's first million selling single?

Answer: bobby darin


Question: Cassandra, Grizabella and Skimbleshanks are all characters in which Andrew Lloyd Webber musical?

Answer: andrew lloyd webber


Question: Which actor starred in the films The China Syndrome and Disclosure?

Answer:
the china syndrome