The minimal polynomial of $\begin{pmatrix} 2 & 1 & 0 & 0\\ 0& 2 & 0 & 0\\ 0& 0 & 2 & 0\\ 0& 0 & 1 & 5 \end{pmatrix}$ is
- $\left ( x-2 \right )\left ( x-5 \right ).$
- $\left ( x-2 \right )^{2}\left ( x-5 \right ).$
- $\left ( x-2 \right )^{3}\left ( x-5 \right ).$
- none of the above.