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: Human rabies is extremely rare, and there have been no cases in Oregon in the last ____ years.\Question: Choose the right answer from options given a) nine b) five c) ten d) eight

A: d
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Q: Conglomerate integration is when ____ apparently unconnected companies merge.\Question: Choose the right answer from options given a) two b) six c) no d) three

A: a
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Q: Most Edwardian castles have ____ concentric rings of walls and towers.\Question: Choose the right answer from options given a) no b) three c) nine d) six

A:
b
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