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: What is the upper most layer of soil?

Answer: What is the upper most layer of soil called?


Question: Who was formula one world champion four times in a row from 2010 to 2013?

Answer: What driver was formula one world champion four times in a row from 2010 to 2013?


Question: Who is the highest paid actor in big bang theory?

Answer:
Based on show salary, who is the highest paid actor on Big Bang Theory?