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: 90 students represent x percent of the boys at jones elementary school . if the boys at jones elementary make up 50 % of the total school population of x students , what is x ? 
Options: a ) 134 , b ) 150 , c ) 225 , d ) 250 , e ) 500
Example Output: a

Example Input: Problem: two numbers are respectively 50 % and 100 % more than a third number . the percentage that is first of the second is ? 
Options: a ) 65 % , b ) 83 % , c ) 27 % , d ) 42 % , e ) 75 %
Example Output: e

Example Input: Problem: a doctor prescribed 18 cubic centimeters of a certain drug to a patient whose body weight was 90 pounds . if the typical dosage is 2 cubic centimeters per 15 pounds of the body weight , by what percent was the prescribed dosage greater than the typical dosage ? 
Options: a ) 8 % , b ) 9 % , c ) 11 % , d ) 12.5 % , e ) 16.7 %
Example Output:
e