```
\item The sum $3-\dfrac{3}{10}+\dfrac{3}{100}-\dfrac{3}{1000} 
      + \cdots + \dfrac{(-1)^k3}{10^k} + \cdots$ is closest to:
\begin{enumerate}
\item[(a)] $\dfrac{2}{e}$
\item[(b)] $2$
\item[(c)] $e$
\item[(d)] $e^2$
\end{enumerate}

```