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: 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: Many comets have ____ tails.\Question: Choose the right answer from options given a) two b) six c) three d) one

Answer: a


Question: Most vertebrates belong in the first ____ groups.\Question: Choose the right answer from options given a) five b) seven c) zero d) three

Answer:
d