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: a man invests rs . 3,000 at the rate of 5 % per annum . how much more should he invest at the rate of 8 % , so that he can earn a total of 6 % per annum ? 
Options: a ) rs . 1200 , b ) rs . 1300 , c ) rs . 1500 , d ) rs . 2000 , e ) none of these
Example Output: c

Example Input: Problem: in a class , if 50 % of the boys were girls , then there would be 50 % more girls than boys . what percentage of the overall class is girls ? 
Options: a ) 25 % , b ) 33.33 % , c ) 40 % , d ) 20 % , e ) 10 %
Example Output: d

Example Input: Problem: there is 60 % increase in an amount in 6 years at si . what will be the ci of rs . 12,000 after 3 years at the same rate ? 
Options: a ) 2372 , b ) 2572 , c ) 4542 , d ) 2343 , e ) 3972
Example Output:
e