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: Birds have ____ eyes.\Question: Choose the right answer from options given a) eight b) five c) nine d) two

A: d
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Q: Color codes are ____ digit combinations of letters and numbers that correspond to a specific color.\Question: Choose the right answer from options given a) six b) eight c) seven d) one

A: a
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Q: Psychiatrists say that ____ out of four people are mentally ill.\Question: Choose the right answer from options given a) eight b) one c) zero d) six

A:
b
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