✔ 最佳答案
Particles A and B have noble gas electronic configurations.
Electronic configurations:
A : 2
B : 2, 8
C : 2, 8, 2
D : 2, 8, 7
E : 2, 8, 7
Electronic configuration is the way that the electrons of an atom is arranged in the electronic shell. It is also known as 'electronic arrangement' or 'electronic structure'.