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: All cattle have a ____ chambered stomach, consisting of a rumen, reticulum, omasum and abomasum.\Question: Choose the right answer from options given a) ten b) four c) six d) two

A: b
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Q: Tadpoles transform within three months, becoming mature adults within ____ year.\Question: Choose the right answer from options given a) one b) zero c) seven d) eight

A:
a
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