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: the compound interest earned by sunil on a certain amount at the end of two years at the rate of 8 % p . a . was rs . 2828.80 . find the total amount that sunil got back at the end of two years in the form of principal plus interest earned ? 
Options: a ) 19828.29 , b ) 19828.2 , c ) 19828.8 , d ) 19828.88 , e ) 19828.21
Example Output: c

Example Input: Problem: the profit earned by selling an article for $ 832 is equal to the loss incurred when the same article is sold for $ 448 . what should be the sale price for making 50 % profit ? 
Options: a ) $ 480 , b ) $ 450 , c ) $ 960 , d ) $ 870 , e ) $ 660
Example Output:
c