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'.

Ex 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

Ex Output:
d


Ex Input:
Problem: what percent of 120 are 90 ? 
Options: a ) 25 % , b ) 50 % , c ) 75 % , d ) 33 % , e ) 30 %

Ex Output:
c


Ex Input:
Problem: the s . i . on a certain sum of money for 3 years at 8 % per annum is half the c . i . on rs . 4000 for 2 years at 10 % per annum . the sum placed on s . i . is ? 
Options: a ) 3000 , b ) 2802 , c ) 1750 , d ) 2990 , e ) 2982

Ex Output:

c