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: if each edge of cube increased by 10 % , the percentage increase in 
Options: a ) 21 , b ) 22 , c ) 25 , d ) 19 , e ) 15

Ex Output:
a


Ex Input:
Problem: what will be the difference between simple and compound interest @ 20 % per annum on a sum of $ 500 after 2 years ? 
Options: a ) $ 10 , b ) $ 20 , c ) $ 25 , d ) $ 30 , e ) $ 40

Ex Output:
b


Ex Input:
Problem: add 15 % of 25 and 12 % of 45 . 
Options: a ) 9.2 , b ) 10.5 , c ) 11.5 , d ) 12.3 , e ) 15

Ex Output:

a