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: Gasoline is ____ times as expensive as in the United States.\Question: Choose the right answer from options given a) two b) four c) three d) ten

A: c
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Q: Mechanical stability comes from having fused quartz, in ____ gravity, cold.\Question: Choose the right answer from options given a) five b) zero c) six d) two

A: b
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Q: Stroke affects more than ____ quarters of a million people every year.\Question: Choose the right answer from options given a) zero b) eight c) three d) seven

A:
c
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