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: Organisms have ____ forms of nucleic acid.\Question: Choose the right answer from options given a) four b) three c) two d) one

A: c
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Q: All butterflies go through ____ life stages .\Question: Choose the right answer from options given a) one b) four c) zero d) five

A: b
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Q: Smoking is responsible for one out of every ____ deaths in the United States.\Question: Choose the right answer from options given a) two b) five c) four d) eight

A:
b
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