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: Kabbalists group the simple letters into ____ triplets.\Question: Choose the right answer from options given a) four b) no c) ten d) three

Answer: a


Question: Argentine ants are able to establish new colonies with as little as ____ worker ants and one queen.\Question: Choose the right answer from options given a) no b) two c) ten d) five

Answer: c


Question: Most aviators serve ____ years after they complete their initial flight training.\Question: Choose the right answer from options given a) five b) eight c) six d) seven

Answer:
d