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: if the simple interest on a sum of money for 4 years at 8 % per annum is rs . 560 , what is the compound interest on the same sum at the rate and for the same time ? 
Options: a ) rs . 640.86 , b ) rs . 430.86 , c ) rs . 330.86 , d ) rs . 630.86 , e ) rs . 130.86
Example Output: d

Example Input: Problem: if the cost price is 94 % of sp then what is the profit % 
Options: a ) 5.07 % , b ) 6 % , c ) 5.7 % , d ) 6.50 % , e ) 6.25 %
Example Output: e

Example Input: Problem: there is 60 % increase in an amount in 6 years at simple interest . what will be the compound interest of $ 12,000 after 3 years at the same rate ? 
Options: a ) $ 2160 , b ) # 3120 , c ) $ 3972 , d ) $ 6240 , e ) none of these
Example Output:
c