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: Condors become sexually mature at about five or ____ years of age and mate for life.\Question: Choose the right answer from options given a) nine b) seven c) one d) six

Answer: d


Question: Nuclear envelopes form around the ____ new nuclei.\Question: Choose the right answer from options given a) two b) eight c) nine d) seven

Answer:
a