The ionic radius of \( \mathrm{Na^+} \) ion is 1.02 Å. The ionic radii (in Å) of \( \mathrm{Mg^{2+}} \) and \( \mathrm{Al^{3+}} \), respectively, are:
\( 0.85 \) and \( 0.99 \)
\( 1.05 \) and \( 0.99 \)
\( 0.72 \) and \( 0.54 \)
\( 0.68 \) and \( 0.72 \)