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: Many people have ____ symptoms until they suffer chest pains or a heart attack.\Question: Choose the right answer from options given a) three b) one c) no d) seven

A: c
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Q: Digital bandwidth enables signal to be condensed as a five to ____ ratio.\Question: Choose the right answer from options given a) one b) nine c) seven d) six

A: a
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Q: Osteoporosis is a very common disorder affecting ____ million people.\Question: Choose the right answer from options given a) ten b) two c) zero d) seven

A:
d
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