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: 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: Respiratory therapists complete two to ____ years of education.\Question: Choose the right answer from options given a) no b) one c) four d) eight

A: c
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Q: Mothers begin to prepare girls to run a household when they are between ____ and nine years old.\Question: Choose the right answer from options given a) seven b) two c) three d) eight

A:
a
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