Question

${\left|A\right|}^2$ cannot be -ve

$\Rightarrow$A and B option cannot be square of matrix

C option is ${\left[\begin{array}{ccc}1& 0& 0\\ 0& 1& 0\\ 0& 0& 1\end{array}\right]}^2$

D option is $\left[\begin{array}{ccc}1& 0& 0\\ 0& 0& 1\\ 0& -1& 0\end{array}\right]$