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: Rock cavies become sexually mature when they are about one to ____ months old.\Question: Choose the right answer from options given a) one b) four c) three d) seven

A: c
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Q: Hummingbirds feed every ____ to fifteen minutes from sun-up to sundown.\Question: Choose the right answer from options given a) nine b) seven c) four d) ten

A: d
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Q: Glasses can be helpful in children as young as ____ months of age.\Question: Choose the right answer from options given a) one b) eight c) seven d) six

A:
d
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