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: Ground squirrels breed once a year, averaging ____ to eight per litter.\Question: Choose the right answer from options given a) seven b) one c) six d) ten

A: a
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Q: Chlorine gives vinyl ____ advantages.\Question: Choose the right answer from options given a) six b) four c) two d) ten

A: c
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Q: Scientists expect all ____ types of neutrinos to be emitted from a supernova.\Question: Choose the right answer from options given a) one b) three c) six d) seven

A:
b
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