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 man deposits $ 2000 in a bank at 4 % per annum and $ 3000 in uti at 14 % per annum . find the rate of interest for the whole sum . 
Options: a ) 15 % , b ) 18 % , c ) 11 % , d ) 17 % , e ) 10 %
Example Output: d

Example Input: Problem: what is the rate percent when the simple interest on rs . 4000 amount to rs . 320 in 2 years ? 
Options: a ) 4 % , b ) 4.1 % , c ) 4.2 % , d ) 4.3 % , e ) 4.5 %
Example Output: a

Example Input: Problem: the profit earned by selling an article for rs . 753 is equal to the loss incurred when the same article is sold for rs . 455 . what should be the sale price for making 50 % profit ? 
Options: a ) 706 , b ) 786 , c ) 906 , d ) 896 , e ) 696
Example Output:
c