Find the Length of the Curve $$y = 2 \ln \left( \sin \frac { x } { 2 } \right) , \frac { \pi } { 3 } \leq x \leq \pi$$

Multiple Choice

Find the length of the curve. Select the correct answer.
$$y = 2 \ln \left( \sin \frac { x } { 2 } \right) , \frac { \pi } { 3 } \leq x \leq \pi$$

A) $\ln ( 2 \sqrt { 3 } )$
B) $\ln ( \sqrt { 3 } )$
C) $\ln ( 3 )$
D) $\ln ( 2 + \sqrt { 3 } )$
E) None of these