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: a reduction of 20 % in the price of salt enables a lady to obtain 10 kgs more for rs . 400 , find the original price per kg ? 
Options: a ) s . 7 , b ) s . 9 , c ) s . 10 , d ) s . 11 , e ) s . 19
Example Output: c

Example Input: Problem: by selling an article at rs . 1000 , a shopkeeper makes a profit of 25 % . at what price should he sell the article so as to make a loss of 25 % ? 
Options: a ) s . 600 , b ) s . 480 , c ) s . 500 , d ) s . 450 , e ) s . 550
Example Output: a

Example Input: Problem: the owner of a furniture shop charges his customer 18 % more than the cost price . if a customer paid rs . 6000 for a computer table , then what was the cost price of the computer table ? 
Options: a ) rs . 6289 , b ) rs . 6298 , c ) rs . 6290 , d ) rs . 5084 , e ) rs . 6708
Example Output:
d