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: a father said to his son , ` ` i was as old as you are at the present at the time of your birth ' ' . if the father ' s age is 52 years now , the son ' s age 5 years back was : 
Options: a ) a ) 14 , b ) b ) 67 , c ) c ) 56 , d ) d ) 21 , e ) e ) 34

Ex Output:
d


Ex Input:
Problem: 16.02 ã — 0.01 = ? 
Options: a ) 0.1602 , b ) 0.001602 , c ) 1.6021 , d ) 0.01602 , e ) none of these

Ex Output:
a


Ex Input:
Problem: find the sum of all 3 digit natural numbers , which are divisible by 8 
Options: a ) 61376 , b ) 54411 , c ) 612314 , d ) 64170 , e ) 64171

Ex Output:

a