The z-transform of the signal
$$x(n) = \begin{cases}1, & n = -1\\2, & n = 0 \\ -1, & n = 1 \\1, & n = 2 \\0, & otherwise \end{cases}$$

A

$$z + 2 - z^{-1} + z^{-2}$$

B

$$z^{-1} + 2 - z + z^2$$

C

$$z + 2z^2 - z^{-1} + z^{-2}$$

D

$$z + 2 - z^{+1} + z^{-2}$$