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: Most internal parasites are specific to one or ____ species.\Question: Choose the right answer from options given a) seven b) three c) two d) five

A: c
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Q: Most infected persons have ____ symptoms of disease.\Question: Choose the right answer from options given a) six b) no c) three d) one

A: b
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Q: Most people tan ____ to three times a week.\Question: Choose the right answer from options given a) zero b) three c) nine d) two

A:
d
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