In this task, you need to answer the given multiple-choice question on the general math. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

Example Input: Problem: if the sales tax reduced from 3 1 / 2 % to 3 1 / 3 % , then what difference does it make to a person who purchases an article with market price of rs . 10800 ? 
Options: a ) 11 , b ) 13 , c ) 14 , d ) 18 , e ) 10
Example Output: d

Example Input: Problem: ages of two sisters differ by 9 years . if 5 years ago , the elder one was twice as old the younger one , find their present age 
Options: a ) 1228 , b ) 1423 , c ) 1632 , d ) 1834 , e ) 1932
Example Output: b

Example Input: Problem: of the 3 - digit integers greater than 700 , how many have two digits t that are equal to each other and the remaining digit different from the other two ? 
Options: a ) 90 , b ) 82 , c ) 80 , d ) 45 , e ) 36
Example Output:
c