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: at what rate percent per annum will the simple interest on a sum of money be 4 / 5 of the amount in 10 years ? 
Options: a ) 4 % , b ) 7 % , c ) 8 % , d ) 3 % , e ) 1 %
Example Output: c

Example Input: Problem: the present worth of a certain bill due sometime hence is rs . 800 and the true discount is rs . 36 . the banker ’ s discount is 
Options: a ) rs . 34.38 , b ) rs . 38.98 , c ) rs . 37 , d ) rs . 37.62 , e ) none
Example Output:
d