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: a reduction of 40 % in the price of bananas would enable a man to obtain 64 more for rs . 40.00001 , what is reduced price per dozen ? 
Options: a ) 6 , b ) 5 , c ) 4 , d ) 3 , e ) 2
Example Output: d

Example Input: Problem: two boys starts from the same place walking at the rate of 5.5 kmph and 7.5 kmph respectively in the same direction . what time will they take to be 32 km apart ? 
Options: a ) 18 , b ) 16 , c ) 19 , d ) 15 , e ) 34
Example Output: b

Example Input: Problem: by selling a book for 290 , 20 % profit was earned . what is the cost price of the book ? 
Options: a ) a ) 215 , b ) b ) 241 , c ) c ) 230 , d ) d ) 235 , e ) e ) 240
Example Output:
b