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: Photosynthesis occurs in ____ phases.\Question: Choose the right answer from options given a) four b) two c) nine d) five

A: b
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Q: Domestic ferrets have ____ restrictions on their range and live throughout the world.\Question: Choose the right answer from options given a) ten b) nine c) no d) seven

A:
c
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