GKFix MCQ Question

Why are Pr, Nd, Tb, and Dy mentioned as exhibiting the +4 state only in oxides (MO₂)?

• A. The +4 state for these elements is stabilized specifically within the oxide lattice structure
• B. The +4 state is the most common state for these elements
• C. These elements cannot form +3 ions
• D. Oxides are the only compounds these elements can form