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'.

Ex Input:
Problem: a car dealership has 40 cars on the lot , 15 % of which are silver . if the dealership receives a new shipment of 80 cars , 30 % of which are not silver , what percentage of total number of cars are silver ? 
Options: a ) 20 % , b ) 25 % , c ) 30 % , d ) 35 % , e ) 40 %

Ex Output:
b


Ex Input:
Problem: if 40 % of a certain number is 160 , then what is 90 % of that number ? 
Options: a ) 270 , b ) 380 , c ) 260 , d ) 360 , e ) 290

Ex Output:
d


Ex Input:
Problem: by selling an article for $ 195 , a person gains $ 45 . what is the gain % ? 
Options: a ) 25 % , b ) 30 % , c ) 50 % , d ) 20 % , e ) 10 %

Ex Output:

b