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'.

Input: Consider Input: Problem: a number increased by 20 % gives 480 . the number is ? 
Options: a ) 200 , b ) 300 , c ) 400 , d ) 500 , e ) 600

Output: c


Input: Consider Input: Problem: in a certain math department , students are required to enroll in either calculus or trigonometry , each of which is offered in beginner and advanced courses . the number of students enrolled in trigonometry is 50 % greater than the number of students enrolled in calculus , and 80 % of calculus students are enrolled in the beginner course . if 4 / 5 of students are in the beginner courses , and one student is selected at random , what is the probability that a beginner trigonometry student is selected ? 
Options: a ) 40 % , b ) 44 % , c ) 48 % , d ) 52 % , e ) 56 %

Output: c


Input: Consider Input: Problem: if an article is sold at 18 % profit instead of 9 % profit , then the profit would be $ 54 more . what is the cost price ? 
Options: a ) $ 500 , b ) $ 600 , c ) $ 700 , d ) $ 800 , e ) $ 900


Output: b