The correct answer is: B. Helium
The first ionization energy is the energy required to remove the most loosely bound electron from an atom in its ground state. The higher the first ionization energy, the more tightly bound the electrons are to the atom.
Helium has the highest first ionization energy of any element in the periodic table. This is because helium has a full valence shell, which means that its electrons are very stable and do not want to be removed.
Hydrogen has the second highest first ionization energy. This is because hydrogen has only one electron in its valence shell, which is not as stable as a full valence shell.
Lithium has the third highest first ionization energy. This is because lithium has two electrons in its valence shell, which are not as stable as a full valence shell.
Sodium has the fourth highest first ionization energy. This is because sodium has one
electron in its valence shell, which is not as stable as a full valence shell.In general, elements with a high electronegativity have a high first ionization energy. This is because elements with a high electronegativity have a strong attraction for electrons, which makes it difficult to remove them from the atom.