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: Foresters usually work ____ hours a day, five days a week.\Question: Choose the right answer from options given a) six b) five c) seven d) eight

A: d
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Q: Elk retain their antlers for more than ____ months of the year.\Question: Choose the right answer from options given a) nine b) ten c) six d) seven

A: c
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Q: Surface water is classified into ____ different classes depending on the cleanliness of the water.\Question: Choose the right answer from options given a) five b) two c) seven d) one

A:
a
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