Which expression below best describes the torque caused by force $F_{2}=T_{\text { M on } \mathrm{B}}$ exerted by the muscle on the backbone?
$\begin{array}{ll}{\text { (a) } 0} & {\text { (b) } F_{2}(2 L / 3) \sin 12^{\circ}} \\ {\text { (c) } F_{2}(L) \cos 30^{\circ}} & {\text { (d) }-F_{2}(2 L / 3) \sin 12^{\circ}}\\ {\text { (e) }-F_{2}(L) \cos 30^{\circ}}\end{array}$
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