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: during a thanksgiving weekend , a car rental company rented 6 - tenths of their vehicles , including two - fifths of the 4 wds that it had . if 40 % of the vehicles are 4 wds , then what percent of the vehicles that were not rented were not 4 wds ? 
Options: a ) 20 % , b ) 30 % , c ) 40 % , d ) 50 % , e ) 60 %

Ex Output:
c


Ex Input:
Problem: the price of a t . v . set worth rs . 15000 is to be paid in 20 installments of rs . 1500 each . if the rate of interest be 6 % per annum , and the first installment be paid at the time of purchase , then the value of the last installment covering the interest as well will be ? 
Options: a ) 29997 , b ) 28088 , c ) 13500 , d ) 19000 , e ) 2799

Ex Output:
c


Ex Input:
Problem: if tim had lunch at $ 60.80 and he gave 20 % tip , how much did he spend ? 
Options: a ) $ 30.60 , b ) $ 60.60 , c ) $ 72.96 , d ) $ 40.60 , e ) $ 50.60

Ex Output:

c