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: if ( x + 3 ) ^ 2 / ( 2 x + 15 ) = 3 , then the difference between the two possible values of x is : 
Options: a ) 8 , b ) 10 , c ) 12 , d ) 14 , e ) 16
Example Output: c

Example Input: Problem: if a person walks at 20 km / hr instead of 10 km / hr , he would have walked 20 km more . the actual distance traveled by him is : 
Options: a ) 20 km , b ) 56 km , c ) 60 km , d ) 70 km , e ) 80 km
Example Output: a

Example Input: Problem: 10 camels cost as much as 24 horses , 16 horses cost as much as 4 oxen and 6 oxen as much as 4 elephants . if the cost of 10 elephants is rs . 170000 , find the cost of a camel ? 
Options: a ) rs . 9800 , b ) rs . 3800 , c ) rs . 9800 , d ) rs . 6800 , e ) rs . 6880
Example Output:
d