$\begin{array}{1 1}(A)\;x=\large\frac{n\pi}{2}+\frac{\pi}{6}&(B)\;x=\large\frac{n\pi}{2}+\frac{\pi}{8}\\(C)\;x=\large\frac{n\pi}{4}+\frac{\pi}{6}&(D)\;x=\large\frac{n\pi}{8}+\frac{\pi}{6}\end{array} $
