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').

Q: All butterflies go through ____ distinct stages in their lives.\Question: Choose the right answer from options given a) eight b) seven c) four d) three

A: c
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Q: Most ovarian cysts go away on their own in ____ to three months without causing any problems.\Question: Choose the right answer from options given a) one b) ten c) five d) eight

A: a
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Q: Astronomers fall in ____ classes - professionals and amateurs.\Question: Choose the right answer from options given a) two b) four c) six d) zero

A:
a
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