In which all have d¹⁰ configuration in their ground state?

To determine which set of elements all have a $d^{10}$ electronic configuration in their ground state, let us analyze the ground-state electronic configurations of the transition metals involved.

Recall the general electronic configuration of transition elements, which is represented as $\left[\text{Noble Gas}\right](n-1)d^{1-10}n{s}^{1-2}$.

Let us write down the ground-state electronic configurations for the elements in the correct option:
1. Copper (Cu, Z = 29):
Copper has an anomalous electronic configuration due to the extra stability associated with a fully filled d-orbital. Instead of the expected $\left[\text{Ar}\right]3d^{9}4s^2$, its actual ground-state configuration is:
$\left[\text{Ar}\right]3d^{10}4s^1$
This confirms a $d^{10}$ configuration.

2. Zinc (Zn, Z = 30):
Zinc is the last element of the first transition series. Its ground-state configuration is:
$\left[\text{Ar}\right]3d^{10}4s^2$
This also features a $d^{10}$ configuration.

3. Silver (Ag, Z = 47):
Similar to copper, silver belongs to Group 11 and exhibits an anomalous configuration to achieve a stable fully filled d-subshell. Its ground-state configuration is:
$\left[\text{Kr}\right]4d^{10}5s^1$
This has a $d^{10}$ configuration.

4. Cadmium (Cd, Z = 48):
Cadmium belongs to Group 12, directly below zinc. Its ground-state configuration is:
$\left[\text{Kr}\right]4d^{10}5s^2$
This also has a $d^{10}$ configuration.

Since all four elements (Cu, Zn, Cd, and Ag) possess a completely filled d-subshell ($d^{10}$) in their ground state, this group of elements satisfies the condition.

Therefore, the correct option is Cu, Zn, Cd, Ag.