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

A: b
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Q: Bytes are sets of ____ bits.\Question: Choose the right answer from options given a) four b) eight c) five d) ten

A: b
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Q: Most population cycles are about three to ____ years in duration.\Question: Choose the right answer from options given a) three b) four c) seven d) two

A:
b
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