In this task, you need to answer the given multiple-choice question on the gain. Gain is the value by which to multiply the input. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

Example Input: Problem: the calendar of the year 2028 can be used again in the year ? 
Options: a ) 2041 , b ) 1951 , c ) 2056 , d ) 1971 , e ) 1973
Example Output: c

Example Input: Problem: a fellow borrowed a certain sum of money at 5 % per annum at simple interest and in 5 years the interest amounted to rs . 2250 less than the sum lent . what was the sum lent ? 
Options: a ) 1050 , b ) 1220 , c ) 1250 , d ) 1060 , e ) 3000
Example Output: e

Example Input: Problem: the salary of a person was reduced by 15 % . by what percent should his reduced salary be raised so as to bring it at par with his original salary ? 
Options: a ) 10 % , b ) 17.6 % , c ) 13.7 % , d ) 15.1 % , e ) 12.3 %
Example Output:
b