In this task, you need to answer the given multiple-choice question on the gain. Gain is the value by which to multiply the input. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

Example Input: Problem: a sum was put at simple interest at a certain rate for 3 years . had it been put at 2 % higher rate , it would have fetched rs . 360 more . find the sum . 
Options: a ) 3000 , b ) 6000 , c ) 2000 , d ) 4000 , e ) none of them
Example Output: b

Example Input: Problem: a trader bought a car at 20 % discount on its original price . he sold it at a 55 % increase on the price he bought it . what percent of profit did he make on the original price ? 
Options: a ) 17 % , b ) 24 % , c ) 12 % , d ) 82 % , e ) 16 %
Example Output: b

Example Input: Problem: a dishonest dealer professes to sell goods at the cost price but uses a weight of 840 grams per kg , what is his percent ? 
Options: a ) 19 , b ) 25 , c ) 77 , d ) 88 , e ) 11
Example Output:
a