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 was put at simple interest at a certain rate for 3 years . had it been put at 2 % higher rate , it would have fetched rs . 360 more . find the sum . 
Options: a ) 3000 , b ) 6000 , c ) 2000 , d ) 4000 , e ) none of them
Example Output: b

Example Input: Problem: a technician makes a round - trip to and from a certain service center by the same route . if the technician completes the drive to the center and then completes 50 percent of the drive from the center , what percent of the round - trip has the technician completed ? 
Options: a ) 70 , b ) 65 , c ) 60 , d ) 75 , e ) 80
Example Output: d

Example Input: Problem: raja spends 35 % of his monthly income on household items , 20 % of his monthly income on buying cloths , 5 % of his monthly income on medicines and saves the remaining amount which is rs . 15000 . find his monthly income . 
Options: a ) rs . 40000 , b ) rs . 36000 , c ) rs . 37500 , d ) rs . 45000 , e ) none of these
Example Output:
c