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 sum fetched a total simple interest of $ 4061.25 at the rate of 9 p . c . p . a . in 5 years . what is the sum ? 
Options: a ) $ 8829 , b ) $ 2840 , c ) $ 6578 , d ) $ 7782 , e ) $ 8926
Example Output: e

Example Input: Problem: what is the compound interest on rs : 40,000 for 4 months at the rate of 5 % per annum 
Options: a ) 670.85 , b ) 671.85 , c ) 672.85 , d ) 673.85 , e ) 674.85
Example Output: a

Example Input: Problem: a sum of money at simple interest amounts to rs . 1072 in 2 years and to rs . 1144 in 4 years . the sum is : 
Options: a ) rs . 1000 , b ) rs . 850 , c ) rs . 500 , d ) rs . 1200 , e ) rs . 900
Example Output:
a