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').

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

[EX Q]: Living cells have at least ____ parts.\Question: Choose the right answer from options given a) seven b) three c) zero d) four
[EX A]: b

[EX Q]: Domestic violence occurs in one out of ____ South Asian families, experts estimate.\Question: Choose the right answer from options given a) one b) ten c) four d) five
[EX A]:
d