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 a lends rs . 2000 to b at 10 % per annum and b lends the same sum to c at 11.5 % per annum then the gain of b in a period of 3 years is ? 
Options: a ) 90 , b ) 122.5 , c ) 132.5 , d ) 114.5 , e ) 212.5
Example Output: a

Example Input: Problem: a money lender finds that due to a fall in the annual rate of interest from 8 % to 7 2 / 7 % his yearly income diminishes by rs . 61.50 . his capital is 
Options: a ) 22.378 , b ) 87.86 , c ) 246.0 , d ) 78.88 , e ) 127.71
Example Output: b

Example Input: Problem: company kw is being sold , and both company a and company b were considering the purchase . the price of company kw is 90 % more than company a has in assets , and this same price is also 100 % more than company b has in assets . if companies a and b were to merge and combine their assets , the price of company kw would be approximately what percent of these combined assets ? 
Options: a ) 66 % , b ) 75 % , c ) 86 % , d ) 97 % , e ) 150 %
Example Output:
d