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: Most children improve in three to ____ days.\Question: Choose the right answer from options given a) seven b) six c) four d) ten

A: a
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Q: Programmable thermostats can change the temperature of a home up to ____ times a day.\Question: Choose the right answer from options given a) four b) ten c) seven d) no

A:
a
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