TASK DEFINITION: In this task, you're given an open-domain question. Your task is to provide an answer to the given question. There is only one unique answer for each question. Your answer should be short, and refer to an entity, date, number, etc. Do not put your answer in the context of a sentence.
PROBLEM: Where did the phantom of the opera play in toronto?

SOLUTION: Pantages Theatre

PROBLEM: Who owns the treasure island in las vegas?

SOLUTION: Phil Ruffin

PROBLEM: What is at the center of a quasar?

SOLUTION:
supermassive black hole