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 price of t . v set is reduced by 10 % , then its sale increases by 85 % , find net effect on sale value 
Options: a ) 44 , b ) 45 , c ) 46 , d ) 67 , e ) 48
Example Output: d

Example Input: Problem: if the difference between compound interest ( interest compounded yearly ) and simple interest on a sum for 3 years at 20 % p . a . is rs . 132 , then the sum is 
Options: a ) rs . 3500 , b ) rs . 1500 , c ) rs . 2500 , d ) rs . 3000 , e ) none
Example Output: e

Example Input: Problem: a man sold 20 articles for $ 60 and gained 20 % . how many articles should he sell for $ 70 to incur a loss 20 % ? 
Options: a ) 45 , b ) 35 , c ) 40 , d ) 50 , e ) 48
Example Output:
b