# Figure caption side by side of the last subfigure

I have a figure consisting of 4 subfigures and a quite long caption. What I would like to do is to have the first three subfigures in the first row and the last one in the second row while the figure's caption is placed side by side of the last subfigure. The objective is economizing the number of pages in my thesis. I saw that the side position for the caption might be possible for a single figure using the "floatrow" package, but in may case, I am using the subfigure package too. I would appreciate it if anyone could help me? Here is an example of my relative part of code and the output I would like to have...

\begin{figure}[htbp]
\centering
\begin{subfigure}{.45\textwidth}
\centering
\caption{}
\end{subfigure}
\begin{subfigure}{.45\textwidth}
\centering
\caption{}
\end{subfigure}
\begin{subfigure}{.45\textwidth}
\centering
\caption{}
\end{subfigure}
\begin{subfigure}{.45\textwidth}
\centering
\caption{}
\end{subfigure}
\caption{Impact of parameter $D$. ....: (a) 11. (b) 12. (c) 13. (d) 14.}
\end{figure}


Once again, minipages are the solution.

\documentclass{article}
\usepackage{mwe}
\usepackage{subcaption}
\begin{document}
\begin{figure}
\centering
\begin{subfigure}{.3\textwidth}
\centering
\includegraphics[width=\linewidth]{example-image}
\caption{}
\end{subfigure}\hfill
\begin{subfigure}{.3\textwidth}
\centering
\includegraphics[width=\linewidth]{example-image-a}
\caption{}
\end{subfigure}\hfill
\begin{subfigure}{.3\textwidth}
\centering
\includegraphics[width=\linewidth]{example-image-b}
\caption{}
\end{subfigure}\medbreak
\begin{subfigure}{.3\textwidth}
\centering
\includegraphics[width=\linewidth]{example-image-c}
\caption{}
\caption{Impact of parameter $D$.  ....: (a) 11.  (b) 12.  (c) 13.  (d) 14.}