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: Psychiatrists say that one in ____ people are mentally ill.\Question: Choose the right answer from options given a) one b) two c) four d) nine

A: c
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Q: Snowflakes are crystals that have many different shapes, but each snowflake has ____ points on it.\Question: Choose the right answer from options given a) six b) nine c) one d) seven

A: a
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Q: Ceiling fans create enough air movement in a room to make it feel cooler by ____ degrees or more.\Question: Choose the right answer from options given a) one b) five c) four d) ten

A:
c
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