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: 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: Parliaments can last five years, often last ____ and a bit.\Question: Choose the right answer from options given a) four b) three c) five d) two

A: a
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Q: Frequent heartburn is defined as heartburn symptoms ____ or more times per week.\Question: Choose the right answer from options given a) five b) ten c) one d) three

A:
d
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