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: All birds have ____ legs with four toes each.\Question: Choose the right answer from options given a) zero b) one c) three d) two

A: d
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Q: Mosquitoes have ____ distinctive life stages, with the first three stages being spent in the water.\Question: Choose the right answer from options given a) four b) zero c) nine d) five

A: a
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Q: Many flightless birds have only ____ toes, the African ostrich but two.\Question: Choose the right answer from options given a) five b) three c) zero d) no

A:
b
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