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: by selling 12 pencils for a rupee a man loses 12 % . how many for a rupee should he sell in order to gain 18 % ? 
Options: a ) 12 , b ) 9 , c ) 10 , d ) 89 , e ) 81
Example Output: a

Example Input: Problem: rs . 1500 is divided into two parts such that if one part is invested at 6 % and the other at 5 % the whole annual interest from both the sum is rs . 86 . how much was lent at 5 % ? 
Options: a ) 388 , b ) 2998 , c ) 277 , d ) 500 , e ) 400
Example Output: e

Example Input: Problem: the cost of one photocopy is $ 0.02 . however , a 25 % discount is offered on orders of more than 100 photocopies . if arthur and david have to make 80 copies each , how much will each of them save if they submit a single order of 160 copies ? 
Options: a ) $ 0.32 , b ) $ 0.40 , c ) $ 0.45 , d ) $ 0.48 , e ) $ 0.54
Example Output:
b