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 problems affect one in ____ school-aged children.\Question: Choose the right answer from options given a) six b) four c) seven d) one
[A]: b


[Q]: Ants have ____ noses.\Question: Choose the right answer from options given a) zero b) eight c) five d) three
[A]: c


[Q]: Recent studies suggest that as many as one couple in ____ suffer from infertility.\Question: Choose the right answer from options given a) nine b) ten c) six d) four
[A]:
c