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: Who sang the song cotton fields back home?

Answer: Who sang the song cotton fields back home in 1940?


Question: Who is the first person to go to the moon?

Answer: Who were the first people to land on the moon?


Question: When did the popular vote for president begin?

Answer:
When did the popular vote for president begin being tracked with a few states participating?