$($c$)$ Consider a unity feedback system, as shown in Figure $7($a$).$ The poles and zeros of $G(s)$ are in Figure $7($b$),$ denoted by $\text{'}x\text{'}$ and $\text{'}O\text{'},$ respectively. Now consider a point $s=-2\mathrm{.}5.$ Which of the following is a true statement.

Figure $7$

$s=-2\mathrm{.}5$ can not be a closed loop pole for any value of $K.$

$s=-2\mathrm{.}5$ is a pole of the closed$-$loop system for $K=\frac{1}{9}.$

$s=-2\mathrm{.}5$ is a pole of the closed$-$loop system for $K=\frac{5}{3}.$

$s=-2\mathrm{.}5$ is a pole of the closed$-$loop system for $K=1.$