Use Reference Angles to Find the Exact Value of the Expression

Multiple Choice

Use reference angles to find the exact value of the expression. Do not use a calculator.
- $\tan \frac { 7 \pi } { 6 }$

A) $\frac { \sqrt { 3 } } { 3 }$
B) $\sqrt { 3 }$
C) $- \sqrt { 3 }$
D) $\frac { \sqrt { 3 } } { 2 }$