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

A: d
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Q: Altimetric satellites are usually limited life missions lasting approximately three to ____ years.\Question: Choose the right answer from options given a) five b) ten c) four d) eight

A: b
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Q: Calves are spotted when born and develop their brown coats in ____ months.\Question: Choose the right answer from options given a) ten b) six c) eight d) four

A:
b
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