Find the Exact Value of the Composition $$\cos ^ { - 1 } \left( \sin \frac { 7 \pi } { 6 } \right)$$

Multiple Choice

Find the exact value of the composition.
- $$\cos ^ { - 1 } \left( \sin \frac { 7 \pi } { 6 } \right)$$

A) $\frac { 2 \pi } { 3 }$
B) $\frac { 4 \pi } { 5 }$
C) $\frac { \pi } { 6 }$
D) $\frac { \pi } { 3 }$