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: Calves can swim ____ days after they are born.\Question: Choose the right answer from options given a) ten b) two c) zero d) one

A: b
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Q: Giraffes sleep less than ____ hours a day.\Question: Choose the right answer from options given a) two b) six c) seven d) ten

A: a
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Q: All proteins possess ____ levels of structure.\Question: Choose the right answer from options given a) no b) one c) three d) ten

A:
c
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