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: Shamrocks can be ____ of four leafs.\Question: Choose the right answer from options given a) six b) seven c) zero d) three

A: d
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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: Electric charge builds up whenever ____ materials are separated.\Question: Choose the right answer from options given a) three b) two c) six d) nine

A:
b
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