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Mustafa was asked whether the following equation is an identity:$\newline$$$x(9 x+3)+3(x+3)=9(x+1)^{2}$$$\newline$He performed the following steps:$\newline$$$x(9 x+3)+3(x+3)$$$\newline$$\stackrel{\text { Step } 1}{\hookrightarrow}=9 x^{2}+6 x+9$$\newline$$\stackrel{\text { Step } 2}{\hookrightarrow}=(3 x+3)^{2}$$\newline$$\stackrel{\text { Step } 3}{\hookrightarrow}=(3(x+1))^{2}$$\newline$$\stackrel{\text { Step } 4}{\hookrightarrow}=9(x+1)^{2}$$\newline$For this reason, Mustafa stated that the equation is a true identity.$\newline$Is Mustafa correct? If not, in which step did he make a mistake?$\newline$Choose $1$ answer:$\newline$(A) Mustafa is correct.$\newline$(B) Mustafa is incorrect. He made a mistake in step $1$.$\newline$(C) Mustafa is incorrect. He made a mistake in step $2$.$\newline$(D) Mustafa is incorrect. He made a mistake in step $4$.