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: an article is bought for rs . 980 and sold for rs . 788 , find the loss percent ? 
Options: a ) 16 % , b ) 19 % , c ) 17 % , d ) 13 % , e ) 12 %
Example Output: b

Example 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 an advanced trigonometry student is selected ? 
Options: a ) 8 % , b ) 12 % , c ) 16 % , d ) 20 % , e ) 24 %
Example Output: b

Example Input: Problem: two tests had the same maximum mark . the pass percentages in the first and the second test were 40 % and 45 % respectively . a candidate scored 231 marks in the second test and failed by 48 marks in that test . find the pass mark in the first test ? 
Options: a ) 768 , b ) 243 , c ) 246 , d ) 625 , e ) 248
Example Output:
e