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: Teething begins for most babies around ____ to six months.\Question: Choose the right answer from options given a) three b) four c) five d) seven

A: b
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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: Harrows come in ____ main types, spring-tooth and disc.\Question: Choose the right answer from options given a) nine b) five c) two d) three

A:
c
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