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 w is the product of the integers from 1 to 30 , inclusive , what is the greatest integer k for which 3 ^ k is a factor of w ? 
Options: a ) 10 , b ) 12 , c ) 14 , d ) 16 , e ) 18

Ex Output:
c


Ex Input:
Problem: find the average of first 4 multiples of 15 ? 
Options: a ) 10 , b ) 12.6 , c ) 22.5 , d ) 31.3 , e ) 37.5

Ex Output:
e


Ex Input:
Problem: in a group of ducks and cows , the total number of legs are 8 more than twice the no . of heads . find the total no . of buffaloes . 
Options: a ) 5 , b ) 4 , c ) 6 , d ) 3 , e ) 2

Ex Output:

b