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: The Brooklyn Bridge crosses which river?
Example Output: brooklyn bridge

Example Input: In which city is the Roslin Institute, the location of the cloning of 'Dolly the Sheep'?
Example Output:
dolly