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: Cats have ____ sets of vocal cords.\Question: Choose the right answer from options given a) zero b) nine c) two d) three

A: c
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Q: Many tractors have ____ wheel drive to get extra grip on the hills and in wet conditions.\Question: Choose the right answer from options given a) four b) seven c) five d) two

A: a
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Q: Chronic unemployment affects one out of ____ workers.\Question: Choose the right answer from options given a) two b) five c) eight d) zero

A:
b
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