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 reduction of 40 % in the price of bananas would enable a man to obtain 64 more for rs . 40.00001 , what is reduced price per dozen ? 
Options: a ) 6 , b ) 5 , c ) 4 , d ) 3 , e ) 2
Example Output: d

Example Input: Problem: a computer store offers employees a 10 % discount off the retail price . if the store purchased a computer from the manufacturer for $ 1200 dollars and marked up the price 10 % to the final retail price , how much would an employee save if he purchased the computer at the employee discount ( 10 % off retail price ) as opposed to the final retail price . 
Options: a ) 122 , b ) 132 , c ) 142 , d ) 152 , e ) 162
Example Output: b

Example Input: Problem: there are 1000 students in a school and among them 25 % of them attends chess class . 50 % of the students who are in the chess class are also enrolled for swimming . no other students are interested in swimming so how many will attend the swimming class if all enrolled attends ? 
Options: a ) 1 , b ) 10 , c ) 125 , d ) 50 , e ) 20
Example Output:
c