In this task, you're given an open-domain question. Your task is to provide an answer to the given question. There is only one unique answer for each question. Your answer should be short, and refer to an entity, date, number, etc. Do not put your answer in the context of a sentence.

Q: Who pays the premium for private healthcare insurance?

A: policy-holder or their sponsor
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Q: Who's the best selling artist of all time?

A: The Beatles
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Q: What is the major cause of water scarcity in south africa?

A:
severe drought
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