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: Most gerbils live three to ____ years and have few health problems.\Question: Choose the right answer from options given a) three b) four c) seven d) zero

A: b
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Q: Ales actively ferment with yeast for two to ____ days.\Question: Choose the right answer from options given a) five b) nine c) three d) six

A: c
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Q: Fossil fuels come in ____ major forms coal, oil and natural gas.\Question: Choose the right answer from options given a) nine b) five c) four d) three

A:
d
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