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Tamara was asked to determine whether $f(x)=x^{4}-2 x^{2}$ is even, odd, or neither. Here is her work:$\newline$Step $1$: Find expression for $f(-x)$$\newline$$$\begin{aligned} f(-x) & =(-x)^{4}-2(-x)^{2} \\ & =x^{4}-2 x^{2} \end{aligned}$$$\newline$Step $2$: Check if $f(-x)$ is equal to $f(x)$ or $-f(x)$$\newline$$x^{4}-2 x^{2}$ is the same as$\newline$$$f(x)=x^{4}-2 x^{2} \text {. }$$$\newline$Step $3$: Conclusion$\newline$$f(-x)$ is equivalent to $f(x)$, so $f$ is even.$\newline$Is Tamara's work correct? If not, what is the first step where Tamara made a mistake?$\newline$Choose $1$ answer:$\newline$(A) Tamara's work is correct.$\newline$(B) Tamara's work is incorrect. She first made a mistake in Step $1$.$\newline$(C) Tamara's work is incorrect. She first made a mistake in Step $2$.$\newline$(D) Tamara's work is incorrect. She first made a mistake in Step $3$.