\documentclass[a4paper, 10pt, fleqn]{article}

\usepackage[utf8]{inputenc}
\usepackage{tikz}
\usepackage{venndiagram}

\begin{document}

\begin{figure}[h!]
	\centering
	\begin{venndiagram2sets}[tikzoptions={scale=0.7}]
		\fillOnlyA;
	\end{venndiagram2sets}
\end{figure}

\end{document}
