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: the difference between the compound interest compounded annually and simple interest for 2 years at 20 % per annum is rs . 72 . find the principal ? 
Options: a ) 2277 , b ) 2667 , c ) 3600 , d ) 2766 , e ) 1800
Example Output: e

Example Input: Problem: what percent of 12.4 kg is 20 gms ? 
Options: a ) 25 , b ) 16 , c ) 18 , d ) 19 , e ) 17
Example Output: b

Example Input: Problem: sarah operated her lemonade stand monday through friday over a two week period and made a total profit of 350 dollars . on hot days she sold cups of lemonade for a price that was 25 percent higher than the regular days . each cup she sold had a total cost of 75 cents and sarah did not incur any other costs . if every day she sold exactly 32 cups and 3 of the days were hot , then what was the price of 1 cup on a hot day ? 
Options: a ) $ 1.50 , b ) $ 1.88 , c ) $ 2.14 , d ) $ 2.50 , e ) $ 3.25
Example Output:
c