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: jackie has two solutions that are 2 percent sulfuric acid and 12 percent sulfuric acid by volume , respectively . if these solutions are mixed in appropriate quantities to produce 60 liters of a solution that is 10 percent sulfuric acid , approximately how many liters of the 12 percent solution will be required ? 
Options: a ) 18 , b ) 20 , c ) 48 , d ) 36 , e ) 42
Example Output: c

Example Input: Problem: a sum of money at simple interest amounts to rs . 415 in 2 years and to rs . 514 in 4 years . the sum is ? 
Options: a ) rs . 316 , b ) rs . 251 , c ) rs . 154 , d ) rs . 294 , e ) rs . 200
Example Output: a

Example Input: Problem: sue ' s trail mix is 30 % nuts and 70 % dried fruit . jane ' s trail mix is 60 % nuts and 40 % chocolate chips . if the combined mixture of sue and jane ' s trails mix contains 35 % nuts , what percent of the combined mixture is dried fruit ? 
Options: a ) 48.3 % , b ) 52.8 % , c ) 55.5 % , d ) 58.3 % , e ) 61.4 %
Example Output:
d