201- The approximate graph of atomic radius variations ($r$) versus the main periodic table quantum number ($Z$) is shown below. Which statement about them is correct? (For noble gases, atomic radius is not defined.) [Figure: Graph of atomic radius $r$ vs atomic number $Z$, showing peaks labeled A, C, E and troughs labeled B, D]
[(1)] D and E are in the halogens group.
[(2)] A and C are in the alkali metals group.
[(3)] B and D are in one period of the periodic table.
[(4)] A and B are in one group of the periodic table.
\textbf{201-} The approximate graph of atomic radius variations ($r$) versus the main periodic table quantum number ($Z$) is shown below. Which statement about them is correct? (For noble gases, atomic radius is not defined.)
\textit{[Figure: Graph of atomic radius $r$ vs atomic number $Z$, showing peaks labeled A, C, E and troughs labeled B, D]}
\begin{enumerate}
\item[(1)] D and E are in the halogens group.
\item[(2)] A and C are in the alkali metals group.
\item[(3)] B and D are in one period of the periodic table.
\item[(4)] A and B are in one group of the periodic table.
\end{enumerate}