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: 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: Calves are born ____ and a half months after mating.\Question: Choose the right answer from options given a) six b) ten c) eight d) two

A: c
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Q: Pertussis is highly contagious with symptoms that can linger ____ to ten weeks.\Question: Choose the right answer from options given a) no b) six c) eight d) two

A:
b
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