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: Sexual maturity is reached at about ____ years of age.\Question: Choose the right answer from options given a) five b) ten c) no d) two

A: d
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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: Wolverine tracks are similar to wolf prints, but a wolf has ____ toes, whereas a wolverine has five.\Question: Choose the right answer from options given a) ten b) six c) four d) eight

A:
c
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