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

Example Input: What is the name of the astromech droid companion of Anakin Skywalker, Luke Skywalker and Obi-Wan Kenobi in the Star Wars franchise?
Example Output: droid

Example Input: Which current Broadway musical has a Japanese therapist character called Christmas Eve?
Example Output: christmas eve

Example Input: Who was the wife of 'King Priam of Troy' and the mother of 'Hector', 'Paris', 'Troilus' and 'Cassandra'?
Example Output:
hector