GKFix MCQ Question

Why is the +3 oxidation state particularly stable for Scandium (Sc), leading to a low E°(M³⁺/M²⁺) value?

• A. Sc³⁺ has a half-filled d-orbital
• B. Sc³⁺ is stabilized by forming complexes
• C. Sc has a very high third ionization energy
• D. The formation of Sc³⁺ results in a stable noble gas electron configuration