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: Statistics show that within ____ years of divorce, many people marry a second time.\Question: Choose the right answer from options given a) four b) nine c) six d) three

Answer: d


Question: Heme is made of ____ pyrrole groups united to form a porphyrin ring.\Question: Choose the right answer from options given a) five b) four c) eight d) six

Answer: b


Question: Ozone is a unique molecule containing ____ oxygen atoms that form an isosceles open triangle.\Question: Choose the right answer from options given a) seven b) two c) ten d) three

Answer:
d