What is the ground-state electron configuration for cadmium (Cd), atomic number 48, in noble-gas shorthand notation?

• A. [Kr] $d^{10}$ $s^1$
• B. [Ar] $d^{10}$ $s^2$
• C. [Kr] $d^8$ $s^2$
• D. [Kr] $d^{10}$ $s^2$

Answer: (D)