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: Mares abort suddenly without signs of illness, and the fetus shows ____ signs of degenerative change.\Question: Choose the right answer from options given a) zero b) no c) seven d) ten

A: b
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Q: Paleontologists specialize in ____ main areas.\Question: Choose the right answer from options given a) eight b) five c) no d) six

A: b
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Q: Veterinarians recommend that a puppy or kitten be at least ____ months old.\Question: Choose the right answer from options given a) four b) ten c) three d) no

A:
a
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