Consider a discrete-time sequence
\[
x[n]=\left\{\begin{array}{ll}
(0.2)^{n}, & 0 \leq n \leq 7 \\
0, & \text { otherwise }
\end{array}\right.
\]
The region of convergence of $X(z)$, the $z$-transform of $x[n]$, consists of
all values of $z$ except $z=0.2$
all values of $z$
all values of $z$ except $z=0$
all values of $z$ except $z=\infty$