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

Answer: b


Question: Ammonia is among the ____ most abundantly produced chemicals in the world.\Question: Choose the right answer from options given a) five b) zero c) no d) eight

Answer: a


Question: Postal codes are six characters long and are a mixture of three letters and ____ numbers.\Question: Choose the right answer from options given a) three b) ten c) four d) seven

Answer:
a