函数 $f(x)=\ln \left(\sin \left(2 x-\frac{\pi}{6}\right)\right)$ 的单调递增区间为（ ）
A. $\left(\frac{\pi}{12}+k \pi, \frac{\pi}{3}+k \pi\right)(k \in Z )$
B. $\left(-\frac{\pi}{6}+k \pi, \frac{\pi}{3}+k \pi\right)(k \in Z )$
C. $\left(\frac{\pi}{3}+k \pi, \frac{7 \pi}{12}+k \pi\right)(k \in Z )$
D. $\left(\frac{\pi}{3}+k \pi, \frac{5 \pi}{6}+k \pi\right)(k \in Z )$