Which one of the following elements exhibit maximum number of valence electrons ?

P – Valence shell electronic configuration is $3{\text{s}}^{2}3{\text{p}}^3$

$\text{Valence\hspace{0.17em}electrons}=2+3=5{\text{e}}^{-}$.

Al – Valence shell electronic configuration is $3{\text{s}}^{2}3{\text{p}}^1$

$\text{Valence\hspace{0.17em}electrons}=2+1=3{\text{e}}^{-}$.

Si – Valence shell electronic configuration is $3{\text{s}}^{2}3{\text{p}}^2$

$\text{Valence\hspace{0.17em}electrons}=2+2=4{\text{e}}^{-}$.

Na – Valence shell electronic configuration is $3{\text{s}}^1$

$\text{Valence\hspace{0.17em}electrons}=1{\text{e}}^{-}$