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: the market value of a certain machine decreased by 10 percent of its purchase price each year . if the machine was purchased in 1982 for its market value of $ 8000 , what was its market value two years later ? 
Options: a ) $ 8,000 , b ) $ 5,600 , c ) $ 3,200 , d ) $ 6,400 , e ) $ 800

Ex Output:
d


Ex Input:
Problem: peter invested a certain sum of money in a simple interest bond whose value grew to $ 100 at the end of 2 years and further to $ 200 at the end of another 4 years . what was the rate of interest in which he invested his sum ? 
Options: a ) 50 % , b ) 25 % , c ) 10 % , d ) 30 % , e ) 18 %

Ex Output:
a


Ex Input:
Problem: the amount of principal rs . 4000 at compound interest at the ratio of 10 % p . a . for 3 years is 
Options: a ) rs . 5342 , b ) rs . 4325 , c ) rs . 5324 , d ) rs . 3425 , e ) rs . 3525

Ex Output:

c