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').
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Question: Most aphthous ulcers heal in one to ____ weeks.\Question: Choose the right answer from options given a) two b) eight c) one d) seven

Answer: a


Question: Unsafe acts cause ____ times as many accidents as unsafe conditions.\Question: Choose the right answer from options given a) no b) eight c) one d) four

Answer: d


Question: Frictional forces cause the ____ plates to be locked together.\Question: Choose the right answer from options given a) two b) four c) one d) eight

Answer:
a