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: 11 + 12 + 13 + . . . 51 + 52 = ? 
Options: a ) 1361 , b ) 1362 , c ) 1323 , d ) 1364 , e ) 1365
Example Output: c

Example Input: Problem: solve the equation for x : 8 x - 40 + 2 x = 5 + 10 - x 
Options: a ) 4 , b ) 10 , c ) 7 , d ) 5 , e ) 3
Example Output: d

Example Input: Problem: 1.45 , 2.56 , 4.78 , 8.11 , 12.55 , ( . . . . ) 
Options: a ) 17.3 , b ) 16.2 , c ) 15.3 , d ) 19.5 , e ) 18.1
Example Output:
e