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 20 % in the price of salt enables a lady to obtain 10 kgs more for rs . 400 , find the original price per kg ? 
Options: a ) s . 7 , b ) s . 9 , c ) s . 10 , d ) s . 11 , e ) s . 19
Example Output: c

Example Input: Problem: a watch was sold at a loss of 21 % . if it was sold for rs . 140 more , there would have been a gain of 4 % . what is the cost price ? 
Options: a ) 560 , b ) 882 , c ) 799 , d ) 778 , e ) 901
Example Output: a

Example Input: Problem: a sum fetched total simple interest of 4016.25 at the rate of 13 p . c . p . a . in 5 years . what is the sum ? 
Options: a ) 6178.85 , b ) 8032.5 , c ) 4462.5 , d ) 8900 , e ) none of these
Example Output:
a