Which of the following statements comprehensively and correctly describe the detailed nature and con — d and f Block Elements Chemistry Question

💡 Solution & Explanation

(A), (B), and (C) correctly define the cause (poor $4f$ shielding), the local effect (shrinking $La$ to $Lu$), and the global periodic table effect (canceling the size gap between $4d$ and $5d$). (D) is completely incorrect; because of the contraction, the $4d$ and $5d$ series end up with highly *similar* properties (like $Zr/Hf$), not divergent ones.