What is the set of solution to the equation $\sqrt{x+6}=x$ ?  $\textasciitilde$ 
选项为:A:$\textbackslash{-2, 3\textbackslash}$  B:$\textbackslash{3\textbackslash}$  C:$\textbackslash{-2\textbackslash}$  D:There are no solutions to the given equation.  请回答其中一个选项.