Simulated photoelectron spectra (PES) for isolated, ground-state atoms of \(\text{Ne}\) (atomic number \(10\)) and \(\text{Na}\) (atomic number \(11\)) are shown below.

Which of the following best explains why the valence electron peak for \(\text{Na}\) appears at a substantially lower binding energy (\(\approx 0.50 \text{ MJ/mol}\)) than the valence electron peak for \(\text{Ne}\) (\(\approx 2.1 \text{ MJ/mol}\)), despite \(\text{Na}\) having a greater nuclear charge (\(Z = 11\)) than \(\text{Ne}\) (\(Z = 10\))?