Let $A = \begin{pmatrix} 0 & 0 & -1 \\ 0 & -1 & 0 \\ -1 & 0 & 0 \end{pmatrix}$. The only correct statement about the matrix $A$ is

Question

( A ) $A^{-1}$ does not exist
( B ) $A$ is a zero matrix
( C ) $A=(-1)I$, where $I$ is a unit matrix
( D ) $A^2 = 1$