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: Studies show that childhood obesity is epidemic and that ____ in five children is overweight.\Question: Choose the right answer from options given a) one b) two c) nine d) ten

A: a
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Q: Natural tellurium consists of ____ isotopes.\Question: Choose the right answer from options given a) six b) seven c) eight d) one

A: c
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Q: Multicellular organisms are made up of ____ or more cells.\Question: Choose the right answer from options given a) ten b) nine c) five d) two

A:
d
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