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: Earthworms have ____ pairs of hearts.\Question: Choose the right answer from options given a) seven b) five c) one d) no

A: b
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Q: Takins can even balance on their hind hooves to nibble on vegetation ____ feet above ground.\Question: Choose the right answer from options given a) two b) no c) nine d) eight

A: d
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Q: Poverty is especially prevalent among rural minorities, who number ____ if four of rural students.\Question: Choose the right answer from options given a) ten b) zero c) five d) one

A:
d
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