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: Illiteracy is ____ percent higher among women than men.\Question: Choose the right answer from options given a) seven b) six c) zero d) five

A: a
****
Q: Some people have ____ symptoms until the liver has been quite severely damaged.\Question: Choose the right answer from options given a) eight b) no c) nine d) ten

A: b
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Q: Volcanoes form in ____ places on the Earth.\Question: Choose the right answer from options given a) nine b) zero c) two d) five

A:
c
****