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: if x is real , find the maximum value of the expression - 2 x ^ 2 + 5 x + 7 .
Options: a ) 6.125 , b ) 8.125 , c ) 10.125 , d ) 12.125 , e ) 14.125

Ex Output:
c

Ex Input:
Problem: find a sum for 1 st 7 prime number ' s ?
Options: a ) 25 , b ) 28 , c ) 58 , d ) 34 , e ) 36

Ex Output:
c

Ex Input:
Problem: the population of a town increased from 1 , 75,000 to 2 , 10,000 in a decade . the average percent increase of population per year is
Options: a ) 2 % , b ) 5 % , c ) 6 % , d ) 8.75 % , e ) none

Ex Output:
a