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: the cost price of a radio is rs . 4800 and it was sold for rs . 4400 , find the loss % ?
Options: a ) 8 , b ) 9 , c ) 7 , d ) 6 , e ) 4
Example Output: a

Example Input: Problem: a , b and c start a business each investing 20,000 . after 10 months a withdrew 5000 , b withdrew 4000 and c invests 6000 more . at the end of the year , a total profit of 71400 was recorded . find the share of b .
Options: a ) 20,000 , b ) 21,200 , c ) 23,200 , d ) 20,500 , e ) none of these
Example Output: c

Example Input: Problem: walking 5 / 4 of his usual rate , a boy reaches his school 4 min early . find his usual time to reach the school ?
Options: a ) 22 , b ) 99 , c ) 27 , d ) 28 , e ) 20
Example Output:
e