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').

Example Input: Natural indium contains ____ isotopes.\Question: Choose the right answer from options given a) one b) eight c) two d) seven
Example Output: c

Example Input: Widowed men are ____ times as likely to be murdered.\Question: Choose the right answer from options given a) two b) four c) three d) no
Example Output: b

Example Input: Domestic Violence tends to follow a cycle of ____ phases.\Question: Choose the right answer from options given a) ten b) three c) eight d) zero
Example Output:
b