Write the Expression as the Sine, Cosine, or Tangent of an Angle

Multiple Choice

Write the expression as the sine, cosine, or tangent of an angle.
- $\frac { \tan ( \pi / 5 ) + \tan ( \pi / 3 ) } { 1 - \tan ( \pi / 5 ) \tan ( \pi / 3 ) }$

A) $\tan \left( \frac { 2 \pi } { 15 } \right)$
B) $\tan \left( \frac { \pi } { 15 } \right)$
C) $\tan \left( \frac { \pi } { 8 } \right)$
D) $\tan \left( \frac { 8 \pi } { 15 } \right)$