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: when greenville state university decided to move its fine arts collection to a new library , it had to package the collection in 20 - inch by 20 - inch by 15 - inch boxes . if the university pays $ 1.30 for every box , and if the university needs 3.06 million cubic inches to package the collection , what is the minimum amount the university must spend on boxes ? 
Options: a ) $ 255 , b ) $ 275 , c ) $ 510 , d ) $ 1,250 , e ) $ 663

Ex Output:
e


Ex Input:
Problem: the sum of three consecutive even numbers multiples of 3 is 72 . what is the largest number ? 
Options: a ) 21 , b ) 24 , c ) 27 , d ) 36 , e ) none

Ex Output:
c


Ex Input:
Problem: 3 , 7,12 , 18,25 . . . . . . . . . . . . . . 9 th terms 
Options: a ) 43 , b ) 53 , c ) 63 , d ) 65 , e ) 78

Ex Output:

c