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 profit earned by selling an article for $ 832 is equal to the loss incurred when the same article is sold for $ 448 . what should be the sale price for making 35 % profit ? 
Options: a ) $ 480 , b ) $ 450 , c ) $ 960 , d ) $ 864 , e ) $ 660
Example Output: d

Example Input: Problem: by selling an article for $ 90 , a person gains $ 15 . what is the gain % ? 
Options: a ) 25 % , b ) 30 % , c ) 50 % , d ) 20 % , e ) 10 %
Example Output: d

Example Input: Problem: a man took loan from a bank at the rate of 12 % p . a . s . i . after 20 years he had to pay rs . 1500 interest only for the period . the principal amount borrowed by him was ? 
Options: a ) 625 , b ) 700 , c ) 950 , d ) 825 , e ) 630
Example Output:
a