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: 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

Ex Output:
b


Ex Input:
Problem: how many 3 - digit positive integers are there , where each digit is positive , and no 3 adjacent digits are same ? 
Options: a ) 1236 , b ) 504 , c ) 4096 , d ) 4608 , e ) 6561

Ex Output:
b


Ex Input:
Problem: what is the least number which should be added to 2697 so that the sum is exactly divisible by 5 , 6 , 4 , and 3 ? 
Options: a ) 3 , b ) 11 , c ) 19 , d ) 27 , e ) 35

Ex Output:

a