HELLO AMIT
for calculating the highest energy of quantum numbers you have to use n+l rule
from the above options
for option no 1 if we use n+l rule
n= 3 and l = 2
so 5
like that if you calculate option B comes out to be as an answer
because,
n = 4 and l = 2 so it is 6 and the highest energy
and no option will come as 6
so option B is the answer
THANK YOU