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: Centrifugal pumps can usually handle up to about ____ percent by volume of air.\Question: Choose the right answer from options given a) one b) five c) eight d) seven
Example Output: b

Example Input: Interdigital glands are present on all ____ feet, and are slightly larger on the front feet.\Question: Choose the right answer from options given a) three b) five c) four d) eight
Example Output: c

Example Input: Cervical cancer is ____ times more common in poor women than in the most affluent.\Question: Choose the right answer from options given a) three b) no c) one d) nine
Example Output:
a