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: uncle bruce is baking chocolate chip cookies . he has 36 ounces of dough ( with no chocolate ) and 10 ounces of chocolate . how much chocolate is left over if he uses all the dough but only wants the cookies to consist of 20 % chocolate ?
Options: a ) 2 , b ) 4 , c ) 6 , d ) 3 , e ) 1
Example Output: e

Example Input: Problem: a man took a loan at rate of 12 % per annum simple interest . after 3 years he had to pay 5400 interest . the principal amount borrowed by him was .
Options: a ) rs 14000 , b ) rs 15000 , c ) rs 16000 , d ) rs 17000 , e ) none of these
Example Output: b

Example Input: Problem: on a purchase of $ 127 , a store offered a payment plan consisting of a $ 27 down payment and 12 monthly payments of $ 10 each . what percent of the purchase price , to the nearest tenth of a percent , did the customer pay in interest by using this plan ?
Options: a ) 18.3 % , b ) 15.3 % , c ) 21.3 % , d ) 22.3 % , e ) 25.3 %
Example Output:
c