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: thirty percent of the members of a swim club have passed the lifesaving test . among the members who have not passed the test , 26 have taken the preparatory course and 65 have not taken the course . how many members are there in the swim club ?
Options: a ) 60 , b ) 80 , c ) 100 , d ) 130 , e ) 140
Example Output: d

Example Input: Problem: the owner of a furniture shop charges his customer 25 % more than the cost price . if a customer paid rs . 8340 for a computer table , then what was the cost price of the computer table ?
Options: a ) rs . 6672 , b ) rs . 6727 , c ) rs . 6908 , d ) rs . 6725 , e ) rs . 6728
Example Output: a

Example Input: Problem: by investing in 1623 % stock at 64 , one earns rs . 1700 . the investment made is
Options: a ) s . 9600 , b ) s . 7500 , c ) s . 5640 , d ) s . 6528 , e ) s . 6760
Example Output:
d