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: Female elephants have babies about ____ years apart, and they have only one each time.\Question: Choose the right answer from options given a) eight b) one c) zero d) three

Answer: d


Question: Many animals use two or ____ forest structure types.\Question: Choose the right answer from options given a) eight b) zero c) two d) three

Answer: d


Question: Pregnant women can get flu shots, preferably after the first ____ months of pregnancy.\Question: Choose the right answer from options given a) four b) three c) ten d) six

Answer:
b