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: When's the last time the angels won the world series?

SOLUTION: When's the last edition the angels won the world series?

PROBLEM: Who sings the song mirror in the bathroom?

SOLUTION: Who sings the song "Mirror in the Bathroom" in 1980?

PROBLEM: Who was the starting quarterback for the vikings?

SOLUTION:
Who was the starting quarterback for the Vikings in 2017?