In this task, you need to answer the given multiple-choice question on the general math. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

Ex Input:
Problem: find out the square of a number which when doubled exceeds its one fifth by 9 ? 
Options: a ) 16 , b ) 25 , c ) 19 , d ) 26 , e ) 17

Ex Output:
b


Ex Input:
Problem: if the price of gasoline increases by 25 % and a driver intends to spend only 5 % more on gasoline , by how much percent should the driver reduce the quantity of gasoline that he buys ? 
Options: a ) 20 % , b ) 16 % , c ) 15 % , d ) 12 % , e ) 10 %

Ex Output:
b


Ex Input:
Problem: if f ( x ) = 12 - x ^ 2 / 2 and f ( 2 k ) = 3 k , what is one possible value for k ? 
Options: a ) 2 , b ) 3 , c ) 4 , d ) 6 , e ) 8

Ex Output:

b