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The Nyquist plot of the transfer function

$$G(s)=\frac{K}{(s^{2}+2s+2)(s+2)}$$

does not encircle the point $(-1+j0)$ for $K=10$ but does encircle the point $(-1+j0)$ for $K=100$. Then the closed loop system (having unity gain feedback) is

- stable for $K=10$ and stable for $K=100$
- stable for $K=10$ and unstable for $K=100$
- unstable for $K=10$ and stable for $K=100$
- stable for $K=10$ and unstable for $K=100$