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: 2525 * 9 
Options: a ) 22725 , b ) 25675 , c ) 22655 , d ) 27575 , e ) none of these
Example Output: a

Example Input: Problem: the ration of the father ’ s age to his son ’ s age is 7 : 3 . the product of their ages is 756 . the ratio of their ages after 6 years will be : 
Options: a ) 5 : 2 , b ) 2 : 1 , c ) 11 : 7 , d ) 13 : 9 , e ) none of these
Example Output: b

Example Input: Problem: from a total of 5 boys and 6 girls , how many 4 - person committees can be selected if the committee must have exactly 2 boys and 2 girls ? 
Options: a ) 16 , b ) 24 , c ) 60 , d ) 120 , e ) 150
Example Output:
e