Which element would have an electron configuration ending in 4d¹⁰?

The correct answer for the element with an electron configuration ending in 4d¹⁰ is Cadmium (Cd). This element is located in the transition metal series, specifically in period 5 of the periodic table and has the atomic number 48.

In terms of electron configuration, Cadmium has a full 4d subshell, indicated by the notation 4d¹⁰. This means it has ten electrons in the 4d orbital, completing this subshell. After filling the 4s subshell (which is filled prior to starting to fill the 4d subshell), the next available orbitals are the 4p, and finally, the 4d orbitals fill up for Cadmium. The complete electron configuration of Cadmium is:

1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 4d¹⁰.

Other elements listed in the choices have different electron configurations that do not correspond to ending in 4d¹⁰. For instance, Silver (Ag) has an electron configuration that ends in 4d¹⁰ 5s¹, indicating