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: Ankle joint has ____ degrees of freedom.\Question: Choose the right answer from options given a) seven b) eight c) four d) three

A: d
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Q: Some programming languages have ____ or more standards.\Question: Choose the right answer from options given a) no b) seven c) two d) three

A: c
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Q: Elephants give birth to one calf every ____ to nine years on average.\Question: Choose the right answer from options given a) no b) four c) three d) seven

A:
b
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