AP Calculus ABhardmcq1 ptIf f(x)=cscxf(x)=\csc xf(x)=cscx, then f′ (π6)=f'\!\left(\frac{\pi}{6}\right)=f′(6π)=A.232\sqrt{3}23B.−23-2\sqrt{3}−23C.−3-\sqrt{3}−3D.−2-2−2