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: fox jeans regularly sell for $ 15 a pair and pony jeans regularly sell for $ 18 a pair . during a sale these regular unit prices are discounted at different rates so that a total of $ 5 is saved by purchasing 5 pairs of jeans : 3 pairs of fox jeans and 2 pairs of pony jeans . if the sum of the two discounts rates is 18 percent , what is the discount rate on pony jeans ? 
Options: a ) 9 % , b ) 10 % , c ) 34.4 % , d ) 12 % , e ) 15 %
Example Output: c

Example Input: Problem: at an election 2 candidates are participated and a candidate got 45 % of votes and defeated by 9000 . and 83 votes are invalid . find the total polled votes ? 
Options: a ) 84512 , b ) 78452 , c ) 65893 , d ) 90083 , e ) 74502
Example Output: d

Example Input: Problem: in a restaurant , the profit is 140 % of the cost . if the cost increases by 12 % but the selling price remains constant , approximately what percentage of the selling price is the profit ? 
Options: a ) 30 % , b ) 53 % , c ) 90 % , d ) 100 % , e ) none of these
Example Output:
b