Find the value of the expression $\cos^{-1} \bigg(\cos \frac{\large 7\pi}{\large 6} \bigg)$

Question

$$\begin{array} (A) \frac{7\pi}{6} \quad & (B) \frac{5\pi}{6} \quad & (C) \frac{\pi}{3} \quad & (D) \frac{\pi}{6} \end{array}$$