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: Classes play ____ distinct roles in object-oriented programming.\Question: Choose the right answer from options given a) eight b) zero c) two d) no

A: c
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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: Grays often hole up for three or ____ days at a time during severe weather.\Question: Choose the right answer from options given a) zero b) four c) two d) no

A:
b
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