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: in order to obtain an income of rs . 1000 from 50 % stock at rs . 500 , one must make an investment of 
Options: a ) rs . 17000 , b ) rs . 16050 , c ) rs . 15400 , d ) rs . 10000 , e ) rs . 10500
Example Output: d

Example Input: Problem: a and b invests rs . 3000 and rs . 7000 respectively in a business . if a doubles his capital after 6 months . in what ratio should a and b divide that year ' s profit ? 
Options: a ) 9 : 6 , b ) 9 : 8 , c ) 9 : 14 , d ) 9 : 9 , e ) 9 : 5
Example Output: c

Example Input: Problem: an article with cost price of 180 is sold at 15 % profit . what is the selling price ? 
Options: a ) 198 , b ) 200 , c ) 204 , d ) 207 , e ) 210
Example Output:
d