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: Military service is fulfilled by voluntary enlistment, generally for a period of ____ years.\Question: Choose the right answer from options given a) four b) one c) nine d) two

A: c
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Q: Respiratory therapists complete ____ to four years of education.\Question: Choose the right answer from options given a) one b) nine c) zero d) two

A: d
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Q: Razor clams have ____ separate genders.\Question: Choose the right answer from options given a) zero b) six c) seven d) two

A:
d
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