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: Vision disorders affect ____ in every four school-age children.\Question: Choose the right answer from options given a) nine b) one c) five d) six

A: b
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Q: Astronomical observations suggest ____ or close to zero space-time curvature.\Question: Choose the right answer from options given a) six b) zero c) ten d) seven

A: b
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Q: Tiny insects suck the life out of the vine, usually taking three to ____ years to fully destroy it.\Question: Choose the right answer from options given a) three b) six c) one d) five

A:
d
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