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

Ex Input:
Richard Addinsell's most famous piece of music was used in the 1941 film 'Dangerous Moonlight', what is its title?

Ex Output:
dangerous moonlight

Ex Input:
Who plays Isobel Crawley in the UK television series 'Downton Abbey'?

Ex Output:
downton abbey

Ex Input:
Which Scottish leader was finally beaten at Culloden?

Ex Output:
battle of culloden