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: Interdigital glands are present on all ____ feet, and are slightly larger on the front feet.\Question: Choose the right answer from options given a) three b) five c) four d) eight

A: c
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Q: Reverse osmosis uses three to ____ gallons of water to produce one gallon of drinking water.\Question: Choose the right answer from options given a) six b) eight c) five d) ten

A: d
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Q: Children are consistently vulnerable to sexual abuse from age ____ on.\Question: Choose the right answer from options given a) ten b) three c) six d) eight

A:
b
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