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: Decapod crustaceans have ____ pairs of limbs.\Question: Choose the right answer from options given a) five b) four c) six d) seven

A: a
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Q: Food waste is transformed into soil-like humus in ____ to seven days.\Question: Choose the right answer from options given a) ten b) five c) zero d) three

A: d
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Q: Girth adjusts ____ ways to fit large horses to ponies.\Question: Choose the right answer from options given a) four b) zero c) nine d) three

A:
d
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