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: Copper is ____ times higher in dog liver than in human liver.\Question: Choose the right answer from options given a) three b) ten c) six d) one

A: b
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Q: Color codes are ____ digit combinations of letters and numbers that correspond to a specific color.\Question: Choose the right answer from options given a) six b) eight c) seven d) one

A: a
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Q: Most smokers go through ____ states of quitting.\Question: Choose the right answer from options given a) one b) four c) five d) three

A:
c
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