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: Tilt consists of ____ small surface vents.\Question: Choose the right answer from options given a) zero b) three c) seven d) no

A: b
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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: Insects have ____ pairs and arachnids have four pairs of limbs.\Question: Choose the right answer from options given a) zero b) three c) four d) ten

A:
b
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