Choose the incorrect trend in the atomic radii (\( r \)) of the elements.
\( r_{\mathrm{Rb}} < r_{\mathrm{Cs}} \)
\( r_{\mathrm{At}} < r_{\mathrm{Cs}} \)
\( r_{\mathrm{Mg}} < r_{\mathrm{Al}} \)
\( r_{\mathrm{Br}} < r_{\mathrm{K}} \)
