Given a sentence with a missing word, pick the answer option that best fills out the missing word in the sentence. Indicate each answer with its index ('a', 'b', 'c', 'd').

Q: Ozone is a molecule containing ____ oxygen atoms.\Question: Choose the right answer from options given a) one b) nine c) no d) three

A: d
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Q: Astronomers fall in ____ classes - professionals and amateurs.\Question: Choose the right answer from options given a) two b) four c) six d) zero

A: a
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Q: Most women die within ____ years.\Question: Choose the right answer from options given a) two b) five c) no d) four

A:
b
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