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: Most children improve in three to ____ days.\Question: Choose the right answer from options given a) seven b) six c) four d) ten
Example Output: a

Example Input: Pairs encodes all sets of objects with ____ components.\Question: Choose the right answer from options given a) ten b) five c) two d) no
Example Output: c

Example Input: Most banks offer checking accounts that have ____ limits on the number of withdrawals each month.\Question: Choose the right answer from options given a) ten b) no c) nine d) five
Example Output:
b