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: Wolverines reproduce every ____ or three years.\Question: Choose the right answer from options given a) two b) three c) one d) four

A: a
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Q: Millipedes have ____ pairs of legs on each body segment.\Question: Choose the right answer from options given a) seven b) ten c) six d) two

A: d
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Q: Any fish can swim near the surface, but it takes a great whale to go down stairs ____ miles or more.\Question: Choose the right answer from options given a) six b) two c) four d) five

A:
d
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