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 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

Ex Output:
a

Ex Input:
Problem: at an election 2 candidates are participated a candidate got 30 % of votes and defeated by 5000 votes . 100 votes are invalid . find the total polled votes ?
Options: a ) 11520 , b ) 12600 , c ) 15000 , d ) 13560 , e ) 12560

Ex Output:
b

Ex Input:
Problem: when the price of an article was reduced by 30 % its sale increased by 80 % . what was the net effect on the sale ?
Options: a ) 26 % increase , b ) 44 % decrease , c ) 60 % increase , d ) 66 % increase , e ) 66 % decrease

Ex Output:
a