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The polar diagram of a conditionally stable system for open loop gain $\text{K}=1$ is shown in the figure. The open loop transfer function of the system is known to be stable. The closed loop system is stable for

1. $\mathrm{K}<5$ and $\frac{1}{2}<\mathrm{K}<\frac{1}{8}$.
2. $\text{K}<\frac{1}{8}$ and $\frac{1}{2} < \text{K} < 5$.
3. $\mathrm{K}<\frac{1}{8}$ and $5<\mathrm{K}$.
4. $\text{K}>\frac{1}{8}$ and $\text{K}<5$.