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: there is 60 lit of milk and water in which milk forms 84 % . howmuch water must be added to this solution to make it solution in which milk forms 64 % 
Options: a ) 18.75 , b ) 19.75 , c ) 20.75 , d ) 21.75 , e ) 22.75

Ex Output:
a


Ex Input:
Problem: a bowl was filled with 10 ounces of water , and 0.014 ounce of the water evaporated each day during a 50 - day period . what percent of the original amount of water evaporated during this period ? 
Options: a ) 0.004 % , b ) 0.04 % , c ) 0.40 % , d ) 7 % , e ) 40 %

Ex Output:
d


Ex Input:
Problem: if the selling price of 7 articles is same as the cost price of 10 articles . find the gain or loss percentage ? 
Options: a ) 93 % , b ) 23 % , c ) 33 % , d ) 43 % , e ) 53 %

Ex Output:

d