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: Vision disorders affect ____ in every four school-age children.\Question: Choose the right answer from options given a) nine b) one c) five d) six
Example Output: b

Example Input: Today there are ____ major breweries in Mexico that produce a spectrum of tasty beverages.\Question: Choose the right answer from options given a) nine b) six c) zero d) eight
Example Output: b

Example Input: Teeth can shine as many as ____ shades brighter.\Question: Choose the right answer from options given a) three b) ten c) four d) two
Example Output:
b