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: what will be the difference between simple and compound interest @ 20 % per annum on a sum of $ 500 after 2 years ? 
Options: a ) $ 10 , b ) $ 20 , c ) $ 25 , d ) $ 30 , e ) $ 40
Example Output: b

Example Input: Problem: 3 candidates in an election and received 1136 , 7636 and 11628 votes respectively . what % of the total votes did the winningcandidate got in that election ? 
Options: a ) 45 % , b ) 56 % , c ) 57 % , d ) 70 % , e ) 72 %
Example Output: c

Example Input: Problem: at what rate percent on simple interest will rs . 750 amount to rs . 825 in 5 years ? 
Options: a ) 2 , b ) 3 , c ) 4 , d ) 5 , e ) 6
Example Output:
a