The correct option is A 5, 25
n is principal quantum number
l is azimuthal quantum number
l ranges from 0 to (n-1)
Given n = 5 So l = 0,1,2,3,4
Number of subshells = 5 (5s,5p,5d,5f,5g)
For s, orbital = 1
For p, orbital = 3
For d, orbital = 5
For f, orbital = 7
For g, orbital = 9
So, total number of orbitals = 25
We can also use the formula as number of orbital = n2
For n = 5, number of orbitals = 25