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: Right whales are slow swimmers, averaging just ____ miles per hour.\Question: Choose the right answer from options given a) nine b) six c) two d) five
Example Output: b

Example Input: Children of alcoholics are ____ times more likely than other people to become alcoholics themselves.\Question: Choose the right answer from options given a) zero b) four c) nine d) two
Example Output: b

Example Input: Psychiatrists say one out of ____ people are mentally ill.\Question: Choose the right answer from options given a) four b) seven c) one d) six
Example Output:
a