You can redefine the `\questionlabel` like this:

```
%\documentclass[12pt,a4paper]{exam}
\documentclass[12pt,a4paper,answers]{exam}

\usepackage[randomize,overload]{exam-randomizechoices}
\newcommand{\correctchoicelabel}{\fbox{\thechoice}}

\usepackage{tikz}

\newcommand*\circled[1]{\tikz[baseline=(char.base)]{%
		\node[shape=circle, draw, minimum size=1.5em, inner sep=0pt , thick] (char) {#1};}}
\renewcommand\choicelabel{\circled{\Alph{choice}}}	
	
\CorrectChoiceEmphasis{\renewcommand{\choicelabel}{\correctchoicelabel}}
\renewcommand{\questionshook}{%
	\settowidth{\leftmargin}{0pt}}
\renewcommand{\choiceshook}{\settowidth{\leftmargin}{\circled{W}.\hskip\labelsep\hskip 0em}}


\renewcommand\questionlabel{Question~\thequestion.}

\begin{document}
	\section{Questions}
	\begin{questions}
		\question What is 2+2?
		\begin{choices}
			\choice 1
			\choice 2
			\choice 3
			\CorrectChoice 4
		\end{choices}

		\question What is 2+2?
		\begin{choices}
			\choice 1
				\CorrectChoice 4
			\choice 2
			\choice 3
		
		\end{choices}
		
		\question What is the result of $1+2$?
		\begin{choices}
			 \choice 1
			 \choice 2
			 \CorrectChoice 3
			 \choice 4
		\end{choices}
	
	\question What is the result of $1+1$?
		\begin{choices}
		 \choice 1
		 \CorrectChoice 2
		 \choice 3
		 \choice 4
	\end{choices}

		\question What is 2+2?
		\begin{choices}
			\choice 1
			\choice 2
			\choice 3
			\CorrectChoice 4
		\end{choices}
		
		\question What is 2+2?
		\begin{choices}
			\choice 1
			\CorrectChoice 4
			\choice 2
			\choice 3
			
		\end{choices}
		
		\question What is the result of $1+2$?
		\begin{choices}
			\choice 1
			\choice 2
			\CorrectChoice 3
			\choice 4
		\end{choices}
		
		\question What is the result of $1+1$?
		\begin{choices}
			\choice 1
			\CorrectChoice 2
			\choice 3
			\choice 4
		\end{choices}		
	\end{questions}
	\subsection{Keys}
	\centering
	\printkeytable
\end{document}
```

![Screenshot 2023-10-16 at 15.34.39.png](/image?hash=44cd4e1a5cebabe1447120ee6d4046a6e599d9c8803b9fc5cb4ccb8c6947ec80)