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: machine a and machine b are each used to manufacture 880 sprockets . it takes machine a 10 hours longer to produce 880 sprockets than machine b . machine b produces 10 % more sprockets per hour than machine a . how many sprockets per hour does machineaproduce ? 
Options: a ) 6 , b ) 6.6 , c ) 8.8 , d ) 100 , e ) 110
Example Output: c

Example Input: Problem: the present worth of rs . 2310 due years hence , the rate of interest being 15 % per annum , is : 
Options: a ) rs . 1440 , b ) rs . 1750 , c ) rs . 1680 , d ) rs . 1840 , e ) none of these
Example Output: c

Example Input: Problem: one - third of 600 is what percent of 120 ? 
Options: a ) 313.2 , b ) 30.1 , c ) 12.24 , d ) none of these , e ) 166.6
Example Output:
e