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: Female elephants have babies about ____ years apart, and they have only one each time.\Question: Choose the right answer from options given a) eight b) one c) zero d) three

Answer: d


Question: Worker bees have ____ pairs of wax glands on the underside of their abdomens.\Question: Choose the right answer from options given a) no b) two c) nine d) four

Answer: d


Question: Verrucous carcinomas are exceptional, with only ____ well-documented cases in the literature.\Question: Choose the right answer from options given a) seven b) nine c) three d) six

Answer:
c