Respuesta :
The answer isĀ D.when the aim is to show electron distributions in shells. This is because there are some instances when elements don't possess a regular or normal electron configuration. There are those who have special electron configurations wherein a lower subshell isn't completely filled before occupying a higher subshell. It is best to visualize such cases using the orbital notation.
Answer: D (When the aim is to show electron distributions in shells)
Explanation: Edge2020