The open loop has one strictly right-half-plane pole at +2; the pole at zero is handled by the usual indented contour. The closed-loop characteristic equation is $s(s-2)+1=(s-1)^2=0$, giving two right-half-plane closed-loop poles. Using clockwise encirclements, $N=Z-P=2-1=1$. Thus the plot makes one clockwise encirclement of −1, A.
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