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: suraj has a certain average of runs for 16 innings . in the 17 th innings he scores 112 runs thereby increasing his average by 6 runs . what is his average after the 17 th innings ? 
Options: a ) 18 , b ) 25 , c ) 16 , d ) 72 , e ) 27

Ex Output:
c


Ex Input:
Problem: if x / y = 7 / 3 , then ( x + y ) / ( x - y ) = ? 
Options: a ) 5 , b ) 5 / 2 , c ) - 1 / 6 , d ) - 1 / 5 , e ) - 5

Ex Output:
b


Ex Input:
Problem: the sum of the ages of 5 children born at the intervals of 3 year each is 40 year . what is the age of the youngest child ? 
Options: a ) 2 year , b ) 8 year , c ) 10 year , d ) none of these , e ) 9 year

Ex Output:

a