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: Reverse osmosis uses three to ____ gallons of water to produce one gallon of drinking water.\Question: Choose the right answer from options given a) six b) eight c) five d) ten

A: d
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Q: China is reportedly in the top ____ nations in industrial output.\Question: Choose the right answer from options given a) seven b) ten c) three d) five

A: b
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Q: Whooping cranes are the tallest birds in North America, standing over ____ feet tall.\Question: Choose the right answer from options given a) six b) ten c) no d) four

A:
d
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