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: Breast cancer strikes one out of every ____ American women.\Question: Choose the right answer from options given a) one b) nine c) no d) six

A: b
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Q: Neutrinos are particles with almost ____ mass and no electric charge.\Question: Choose the right answer from options given a) no b) two c) zero d) five

A: a
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Q: Water scorpions regulate their depth using ____ pairs of special sensors on their bellies.\Question: Choose the right answer from options given a) three b) four c) zero d) nine

A:
a
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