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.
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Question: Where is the x factor final 2017 filmed?

Answer: In what building is the x factor final 2017 filmed?


Question: Where would the highest density of mangrove forests be found?

Answer: What country has the largest percentage of the world's mangrove forests?


Question: Who has the best winning percentage in nfl history?

Answer:
What team has the best regular season winning percentage in NFL history?