TASK DEFINITION: In this task, you're given an ambiguous question (which can be answered in more than one way). Your task is to write a question that clarifies the given question in such a way that the generated question has one unique answer.
PROBLEM: What is the largest populated city in the us?

SOLUTION: What is the largest populated city in the US based on a 2018 estimate?

PROBLEM: When did the first episode of dragonball air?

SOLUTION: When did the first episode of dragonball air in Japan?

PROBLEM: When did phantom of the opera movie come out?

SOLUTION:
When did the 1925 The Phantom of the Opera movie come out?