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: 48.95 - 32.006 = ? 
Options: a ) 16.089 , b ) 16.35 , c ) 16.89 , d ) 16.944 , e ) none of them

Ex Output:
d


Ex Input:
Problem: ( 18 ) 7 x ( 5832 ) - 2 ÷ ( 324 ) - 1 = ( 18 ) 7 
Options: a ) 5 , b ) 4 , c ) 3 , d ) 2 , e ) 1

Ex Output:
c


Ex Input:
Problem: the sum of three consecutive multiples of 3 is 117 . what is the largest number ? 
Options: a ) 45 , b ) 48 , c ) 51 , d ) 42 , e ) 54

Ex Output:

d