What is the characteristic polynomial of the matrix A=(0001001001001000)A = \begin{pmatrix} 0 & 0 & 0 & 1 \\ 0 & 0 & 1 & 0 \\ 0 & 1 & 0 & 0 \\ 1 & 0 & 0 & 0 \end{pmatrix}A=0001001001001000?
(λ−1)2(λ+1)2(\lambda - 1)^2(\lambda + 1)^2(λ−1)2(λ+1)2
λ4−1\lambda^4 - 1λ4−1
(λ2−1)2(\lambda^2 - 1)^2(λ2−1)2
λ4+1\lambda^4 + 1λ4+1