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 is 50 % of 40 % of 1200 grams ?
Options: a ) 450 gms , b ) 100 gms , c ) 300 gms , d ) 240 gms , e ) none of these
Example Output: d

Example Input: Problem: ravi and kavi start a business by investing a ' 4000 and a ' 72000 , respectively . find the ratio of their profits at the end of year .
Options: a ) 2 : 28 , b ) 5 : 28 , c ) 7 : 18 , d ) 1 : 18 , e ) 3 : 18
Example Output: d

Example Input: Problem: a certain sum is invested at simple interest at 18 % p . a . for two years instead of investing at 12 % p . a . for the same time period . therefore the interest received is more by rs . 600 . find the sum ?
Options: a ) 7000 , b ) 7029 , c ) 2778 , d ) 2800 , e ) 5000
Example Output:
e