Convert from Rectangular to Trigonometric Form $\theta$ Such That $0 \leq \theta < 2 \pi$

Multiple Choice

Convert from rectangular to trigonometric form. (Choose an argument $\theta$ such that $0 \leq \theta < 2 \pi$ .) $- \frac { 1 } { 2 } + \frac { 1 } { 2 } \sqrt { 3 } i$

A) $\frac { 1 } { 2 } \left( \cos \frac { 2 \pi } { 3 } + i \sin \frac { 2 \pi } { 3 } \right)$
B) $\frac { 1 } { 2 } \left( \sin \frac { 2 \pi } { 3 } + i \cos \frac { 2 \pi } { 3 } \right)$
C) $\left( \cos \frac { 2 \pi } { 3 } - i \sin \frac { 2 \pi } { 3 } \right)$
D) $\left( \sin \frac { 2 \pi } { 3 } - i \cos \frac { 2 \pi } { 3 } \right)$
E) $\left( \cos \frac { 2 \pi } { 3 } + i \sin \frac { 2 \pi } { 3 } \right)$