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: Carbon can bond to a maximum of ____ atoms.\Question: Choose the right answer from options given a) six b) ten c) five d) four

A: d
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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: Asian women are ____ times more likely to attempt suicide than their white counterparts.\Question: Choose the right answer from options given a) zero b) eight c) three d) no

A:
c
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