Use the Given Triangles to Evaluate the Expression $\cos \frac { \pi } { 6 }$

Multiple Choice

Use the given triangles to evaluate the expression. Rationalize all denominators.
- $\cos \frac { \pi } { 6 }$

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