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

Example Input: In which book of the Bible are the Ten Commandments first mentioned?
Example Output: bible

Example Input: Which Dickens novel is subtitled The Parish Boy's Progress?
Example Output: charles dickens

Example Input: Which was the title of the 7th and final book in the Chronicles of Narnia by C.S. Lewis?
Example Output:
the chronicles of narnia