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: Acoustic guitars come in ____ types.\Question: Choose the right answer from options given a) two b) ten c) one d) four

Answer: a


Question: Gorillas live in groups than can range between ____ and thirty members.\Question: Choose the right answer from options given a) five b) nine c) two d) six

Answer:
a