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').
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Question: Most birds have ____ toes, three that face forward and one rearward.\Question: Choose the right answer from options given a) two b) ten c) nine d) four

Answer: d


Question: Some olive trees live to be ____ thousand years old.\Question: Choose the right answer from options given a) ten b) zero c) two d) seven

Answer: c


Question: Infertility is a disease that affects approximately ____ in ten couples worldwide.\Question: Choose the right answer from options given a) zero b) ten c) one d) five

Answer:
c