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'.

[EX Q]: Problem: how much 60 % of 50 is greater than 30 % of 30 ? 
Options: a ) 21 , b ) 91 , c ) 11 , d ) 17 , e ) 12
[EX A]: a

[EX Q]: Problem: by selling an article for $ 110 , a person gains $ 10 . what is the gain % ? 
Options: a ) 25 % , b ) 30 % , c ) 50 % , d ) 20 % , e ) 10 %
[EX A]: e

[EX Q]: Problem: a man spends 35 % of his income on food , 25 % on children education and 80 % of the remaining on house rent . what percent of his income he is left with ? 
Options: a ) 1 % , b ) 8 % , c ) 12 % , d ) 5 % , e ) 4 %
[EX A]:
b