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: 120 + 520 ÷ 5.00 = ? 
Options: a ) 100 , b ) 150 , c ) 120 , d ) 520 , e ) none
Example Output: e

Example Input: Problem: a , b and c rents a pasture for rs . 1073 . a put in 12 horses for 8 months , b 16 horses for 9 months and 18 horses for 6 months . how much should c pay ? 
Options: a ) 270 , b ) 289 , c ) 267 , d ) 255 , e ) 333
Example Output: e

Example Input: Problem: a room is 7 meters 20 centimeters in length and 4 meters 32 centimeters in width . find the least number of square tiles of equal size required to cover the entire floor of the room . 
Options: a ) 10 , b ) 15 , c ) 17 , d ) 19 , e ) 21
Example Output:
b