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: if the cost price of 55 articles is equal to the selling price of 50 articles , then what is the percent profit ? 
Options: a ) 5 % , b ) 10 % , c ) 15 % , d ) 20 % , e ) 25 %
Example Output: b

Example Input: Problem: a man deposits $ 2000 in a bank at 4 % per annum and $ 3000 in uti at 14 % per annum . find the rate of interest for the whole sum . 
Options: a ) 15 % , b ) 18 % , c ) 11 % , d ) 17 % , e ) 10 %
Example Output: d

Example Input: Problem: indu gave bindu rs . 4375 on compound interest for 2 years at 4 % per annum . how much loss would indu has suffered had she given it to bindu for 2 years at 4 % per annum simple interest ? 
Options: a ) s . 10 , b ) s . 7 , c ) s . 5 , d ) s . 3 , e ) s . 4
Example Output:
b