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').
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Question: Most bioluminescence is blue for ____ reasons.\Question: Choose the right answer from options given a) seven b) two c) four d) zero

Answer: b


Question: Some European countries require ____ years of education.\Question: Choose the right answer from options given a) no b) nine c) six d) three

Answer: d


Question: Compulsive Disorder affects about sixty- ____ per ten thousand people in any given year.\Question: Choose the right answer from options given a) nine b) seven c) two d) no

Answer:
a