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: Cows breed at ____ years, bulls at four.\Question: Choose the right answer from options given a) two b) three c) seven d) one

A: b
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Q: Vision problems affect one in ____ school-aged children.\Question: Choose the right answer from options given a) six b) four c) seven d) one

A: b
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Q: Elephants have only ____ molars in use at a time.\Question: Choose the right answer from options given a) six b) four c) zero d) five

A:
b
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