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: Stable oxygen has eight protons and ____ neutrons.\Question: Choose the right answer from options given a) eight b) ten c) three d) zero

A: a
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Q: Voles are prolific breeders and can produce four to ____ litters a year.\Question: Choose the right answer from options given a) four b) two c) six d) three

A: c
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Q: Climate covers minimum and maximum temperatures for all ____ seasons.\Question: Choose the right answer from options given a) two b) nine c) four d) one

A:
c
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