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: on a sum of money , the s . i . for 2 years is $ 600 , while the c . i . is $ 612 , the rate of interest being the same in both the cases . the rate of interest is ? 
Options: a ) 3 % , b ) 4 % , c ) 5 % , d ) 6 % , e ) 7 %
Example Output: b

Example Input: Problem: a bowl of fruit contains 14 apples and 20 oranges . how many oranges must be removed so that 70 % of the pieces of fruit in the bowl will be apples ? 
Options: a ) 3 , b ) 6 , c ) 14 , d ) 17 , e ) 20
Example Output: c

Example Input: Problem: the difference between simple interest and compound interest on $ 1200 for one year at 10 % per annum reckoned half - yearly is : 
Options: a ) $ 5 , b ) $ 8 , c ) $ 9 , d ) $ 3 , e ) $ 7
Example Output:
d