Correct order of first ionization potentials

A)  $\text{K}<\text{Na}$                  C)$\text{Mg}>\text{Ca}$

$\text{Na}=\left[\text{Ne}\right]3{\text{s}}^1$           $\text{K}=\left[\text{Ar}\right]4{\text{s}}^1$

When compared K, Na has highest ionization energy. Due to I.E decreases top to bottom in a group.

 C) $\text{Mg}>\text{Ca, Mg}=\left[\text{Ne}\right]3{\text{s}}^2\text{\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}Ca}=\left[\text{Ar}\right]4{\text{s}}^2$

When compared Mg, Ca Mg has highest ionization energy. Due to I.E decreases top to bottom in a group.