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: 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: Litters contain from one to ____ kittens, and tend to be much larger when prey is abundant.\Question: Choose the right answer from options given a) three b) four c) two d) seven

A: b
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Q: Value is a relative fact that varies in significance from ____ to infinity.\Question: Choose the right answer from options given a) four b) nine c) three d) zero

A:
d
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