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Let the open loop transfer function $L(s)=\frac{(s-6{)}^2+25}{(s+2{)}^2(s-5)}.$ Fig. $8$ shows the Nyquist plot of $L(s).$ The Nyquist contour is a semicircle centered at the origin which encircles the entire right half of the complex plane in a clockwise direction. Which of the following statements about the closed$-$loop transfer function $T(s)$:$=\frac{L(s)}{1+L(s)}$ is true?

Figure $8$: The Nyquist plot of $L(s).$

$($A$)T(s)$ has two unstable poles.

$($B$)T(s)$ is stable.

$($C$)T(s)$ has three unstable poles.

$($D$)$ None of the above.

a$.($A$)$

b$.($B$)$

c$.($C$)$

d$.($D$)$