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: jar a has 6 % more marbles than jar b . what percent of marbles from jar a need to be moved into jar b so that both jars have equal marbles ? 
Options: a ) 2.8 % , b ) 3.0 % , c ) 3.2 % , d ) 3.4 % , e ) 3.6 %
Example Output: a

Example Input: Problem: a baseball card decreased in value 10 % in its first year and 10 % in its second year . what was the total percent decrease of the card ' s value over the two years ? 
Options: a ) 19 % , b ) 30 % , c ) 32 % , d ) 36 % , e ) 72 %
Example Output: a

Example Input: Problem: rs . 600 amounts to rs . 900 in 3 years at simple interest . if the interest is increased by 4 % , it would amount to how much ? 
Options: a ) 672 , b ) 246 , c ) 258 , d ) 856 , e ) 653
Example Output:
a