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'.

Ex Input:
Problem: raman ' s salary was decreased by 50 % and subsequently increased by 50 % . how much percent does he loss .
Options: a ) 75 , b ) 65 , c ) 45 , d ) 25 , e ) 85

Ex Output:
d

Ex Input:
Problem: a broker invested her own money in the stock market . during the first year , she increased her stock market wealth by 60 percent . in the second year , largely as a result of a slump in the stock market , she suffered a 30 percent decrease in the value of her stock investments . what was the net increase or decrease on her overall stock investment wealth by the end of the second year ?
Options: a ) 5 % , b ) 5 % , c ) 12 % , d ) 20 % , e ) 80 %

Ex Output:
c

Ex Input:
Problem: a 6 litre sol is 35 % alcohol . how many litres of pure alcohol must be added to produce a sol that is 50 % alcohol ?
Options: a ) a . 0.6 , b ) b . 1 , c ) c . 2.1 , d ) d . 1.8 , e ) e . 5.4

Ex Output:
d