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: given f ( x ) = 3 x – 5 , for what value of x does 2 * [ f ( x ) ] – 10 = f ( x – 2 ) ? 
Options: a ) 1 , b ) 2 , c ) 3 , d ) 4 , e ) 5
Example Output: c

Example Input: Problem: a sum of money is to be distributed among a , b , c , d in the proportion of 5 : 2 : 4 : 3 . if c gets rs . 2000 more than d , what is b ' s share ? 
Options: a ) a ) 4000 , b ) b ) 2900 , c ) c ) 2000 , d ) d ) 2393 , e ) e ) 2009
Example Output: a

Example Input: Problem: ( 2 ^ 2 + 4 ^ 2 + 6 ^ 2 + . . . . . + 14 ^ 2 ) = ? 
Options: a ) 88 , b ) 560 , c ) 99 , d ) 550 , e ) 540
Example Output:
b