GKFix MCQ Question

Why are ns electrons lost before (n-1)d electrons when d-block elements form ions?

• A. The ns orbitals are lower in energy than the (n-1)d orbitals
• B. The ns orbitals are higher in energy than the (n-1)d orbitals in the ground state of transition metal atoms
• C. The ns electrons are closer to the nucleus
• D. The (n-1)d electrons are more stable