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').

[EX Q]: Breast cancer strikes one out of every ____ American women.\Question: Choose the right answer from options given a) one b) nine c) no d) six
[EX A]: b

[EX Q]: 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
[EX A]: d

[EX Q]: Arthropods are made up of ____ groups of living animals and one group of extinct animals.\Question: Choose the right answer from options given a) no b) six c) eight d) four
[EX A]:
d