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: Potassium helps maintain fluid regulation and normal pH. All ____ help normalize.\Question: Choose the right answer from options given a) three b) six c) two d) one

A: a
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Q: Statistics show, however, that men are ____ times more likely to be lefty than women.\Question: Choose the right answer from options given a) four b) three c) nine d) two

A: b
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Q: Sharks use ____ different methods of reproduction.\Question: Choose the right answer from options given a) six b) eight c) four d) three

A:
d
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