The first ionization energies and ground-state valence electron configurations for four Period 2 elements are shown in the table below.

Element	Valence Electron Configuration	First Ionization Energy (\(\text{kJ/mol}\))
\(\text{Be}\)	\(2s^2\)	\(899\)
\(\text{B}\)	\(2s^2\,2p^1\)	\(801\)
\(\text{N}\)	\(2s^2\,2p^3\)	\(1402\)
\(\text{O}\)	\(2s^2\,2p^4\)	\(1314\)

Although first ionization energy generally increases across a period with increasing nuclear charge, both \(\text{B}\) and \(\text{O}\) have lower first ionization energies than the preceding element. Which of the following statements provides the correct justification for both observed anomalies based on subshell electron configurations?