Identify the features of the two bonded amino acids depicted below

I found a similar problem from another website with the same problem which is shown in the picture attached below. The choices are given on the right which are highlighted in blue. Let's answer this by starting from left of the structure to the right.

1. NH₂ is an amino group.
2. The long chain is a hydrophilic side chain. This is because amines are very solube in water.
3. The middle group is called the peptide bond, which connects two amino acids together.
4. The hydrocarbon chain is a hydrophobic side chain.It is named as such because it is nonpolar.
5. The rightmost structure is a carboxyl group.

The problem here is that according to aufbau principle before 3d orbital 4s subshell comes.after filling 3p orbital with electrons you have 4 electrons left, you place two in 4s with opposite spin and the other two in 3d in any of its two orbitals of total five orbitals with the same spin.