Match the Column I with Column II.
\begin{tabular}{|l|l|l|l|}
\hline \multicolumn{2}{|c|}{ Column I } & \multicolumn{2}{c|}{ Column II } \\
\hline (i) & An electric cell & (a) & (•) \\
\hline (ii) & Electric bulb & (b) \\
\hline (iii) & Resistance & (c) & \\
\hline (iv) & Plug key (or) switch (closed) & (d) & \\
\hline
\end{tabular}