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 total of $ 20,000 was invested in two certificates of deposit at simple annual interest rates of 4 percent and 8 percent , respectively . if the total interest on the two certificates was $ 1,440 at the end of one year , what fractional part of the $ 20.000 was invested at the higher rate ? 
Options: a ) 3 / 8 , b ) 4 / 5 , c ) 1 / 2 , d ) 3 / 5 , e ) 3 / 4
Example Output: b

Example Input: Problem: 150 is what percent of 60 ? 
Options: a ) 250 % , b ) 20 % , c ) 50 % , d ) 200 % , e ) 500 %
Example Output: a

Example Input: Problem: the number which exceeds 16 % of it by 84 is : 
Options: a ) 100 , b ) 52 , c ) 58 , d ) 60 , e ) 62
Example Output:
a