In period 4 of the periodic table which elements have the highest and lowest atomic radii respectively． （A） K and Br （B）Na and Cl （C）K and Se （D） Rb and Br
In period 4 of the periodic table which elements have the highest and lowest atomic radii respectively．
（A） K and Br
（B）Na and Cl
（C）K and Se
（D） Rb and Br