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

Example Input: The Byzantine Empire is the term used since the 19th century to describe the Roman Empire of the Middle Ages, centred on its capital, where?
Example Output: byzantine empire

Example Input: Which singer played Billie Holiday in the 1972 film `Lady Sings The Blues`?
Example Output: lady sings the blues

Example Input: The Fox Islands, Islands of Four Mountains, Andreanof Islands, Rat Islands, Buldir Island, Commander Islands and Near Islands are all part of which island chain?
Example Output:
buldir island