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: Blood pressure is measured by ____ numbers.\Question: Choose the right answer from options given a) zero b) eight c) two d) seven

A: c
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Q: Humans normally produce only ____ sets of teeth.\Question: Choose the right answer from options given a) nine b) eight c) two d) three

A: c
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Q: Canaries have ____ distinct feather types.\Question: Choose the right answer from options given a) seven b) two c) six d) one

A:
b
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