Which of the following representation of atomic orbitals is CORRECT...

According to the $(n+l)$ rule, the energy of an orbital depends on the sum of the principal quantum number $(n)$ and the azimuthal quantum number $(l)$. If two orbitals have the same $(n+l)$ value, the orbital with the lower $n$ value has lower energy.

For $3s$ and $2p$:
$3s: n+l = 3+0 = 3$
$2p: n+l = 2+1 = 3$
Since $n$ is lower for $2p$, $2p < 3s$.

For $4s$ and $3p$:
$4s: n+l = 4+0 = 4$
$3p: n+l = 3+1 = 4$
Since $n$ is lower for $3p$, $3p < 4s$.

For $3d$ and $4p$:
$3d: n+l = 3+2 = 5$
$4p: n+l = 4+1 = 5$
Since $n$ is lower for $3d$, $3d < 4p$. This representation is correct.

For $5s$ and $4p$:
$5s: n+l = 5+0 = 5$
$4p: n+l = 4+1 = 5$
Since $n$ is lower for $4p$, $4p < 5s$.

Answer: $3d < 4p$