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'.

Example Input: Problem: a case contains c cartons . each carton contains b boxes , and each box contains 200 paper clips . how many paper clips are contained in 2 cases ? 
Options: a ) 200 bc , b ) 200 b / c , c ) 400 bc , d ) 400 b / c , e ) 400 / bc
Example Output: c

Example Input: Problem: ( 112 x 5 ^ 4 ) = ? 
Options: a ) 70000 , b ) 80000 , c ) 90000 , d ) 90090 , e ) 100000
Example Output: a

Example Input: Problem: there are 6 boxes numbered 1 , 2 , … , . 6 . each box is to be filled up either with a red or a green ball in such a way that at least 1 box contains a green ball and the boxes containing green balls are consecutively numbered . the total number of ways in which this can be done is 
Options: a ) 22 , b ) 21 , c ) 45 , d ) 27 , e ) 25
Example Output:
b