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: Whales are divided into ____ categories, based on their teeth.\Question: Choose the right answer from options given a) two b) four c) nine d) ten

Answer: a


Question: Metals often crystallize in a ____ dimensional version of the hexagonal closest packed structure.\Question: Choose the right answer from options given a) one b) seven c) three d) eight

Answer: c


Question: Wine comes in a variety of flavors, but there are only ____ basic types.\Question: Choose the right answer from options given a) one b) nine c) six d) three

Answer:
d