What is the electron configuration of ${\text{S}}{{\text{n}}^{2 + }}$?

A.     $1{{\text{s}}^2}2{{\text{s}}^2}2{{\text{p}}^6}3{{\text{s}}^2}3{{\text{p}}^6}4{{\text{s}}^2}3{{\text{d}}^{10}}4{{\text{p}}^6}5{{\text{s}}^2}4{{\text{d}}^{10}}5{{\text{p}}^2}$

B.     $1{{\text{s}}^2}2{{\text{s}}^2}2{{\text{p}}^6}3{{\text{s}}^2}3{{\text{p}}^6}4{{\text{s}}^2}3{{\text{d}}^{10}}4{{\text{p}}^6}5{{\text{s}}^2}4{{\text{d}}^{10}}$

C.     $1{{\text{s}}^2}2{{\text{s}}^2}2{{\text{p}}^6}3{{\text{s}}^2}3{{\text{p}}^6}4{{\text{s}}^2}3{{\text{d}}^{10}}4{{\text{p}}^6}4{{\text{d}}^{10}}5{{\text{p}}^2}$

D.     $1{{\text{s}}^2}2{{\text{s}}^2}2{{\text{p}}^6}3{{\text{s}}^2}3{{\text{p}}^6}4{{\text{s}}^2}3{{\text{d}}^{10}}4{{\text{p}}^6}5{{\text{s}}^2}4{{\text{d}}^8}5{{\text{p}}^2}$

B