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: Giraffes sleep less than ____ hours a day.\Question: Choose the right answer from options given a) two b) six c) seven d) ten

A: a
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Q: Young squirrels remain in the nest for about ____ weeks.\Question: Choose the right answer from options given a) seven b) six c) two d) eight

A: b
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Q: Radon causes ____ symptoms of irritation and no acute illness.\Question: Choose the right answer from options given a) five b) four c) six d) no

A:
d
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