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'.

Example Input: Problem: ( x + 3 ) is a factor in x ^ 2 - mx - 15 . what is the value of m ? 
Options: a ) 1 , b ) 2 , c ) 3 , d ) 4 , e ) 5
Example Output: b

Example Input: Problem: for what value of x between − 8 and 8 , inclusive , is the value of x ^ 2 − 10 x + 16 the greatest ? 
Options: a ) − 8 , b ) − 2 , c ) 0 , d ) 2 , e ) 8
Example Output: a

Example Input: Problem: the present ages of 3 persons are in proportions 4 : 7 : 9 . 7 years ago , the sum of their ages was 79 . find their present ages . 
Options: a ) 20 , 28 , b ) 28 , 36 , c ) 35 , 45 , d ) 35 , 55 , e ) of these
Example Output:
c