Find the Exact Value of the Expression, If Possible $$\tan \left( \sec ^ { - 1 } \frac { \sqrt { x ^ { 2 } + 9 } } { x } \right)$$

Multiple Choice

Find the exact value of the expression, if possible. Do not use a calculator.
- $$\tan \left( \sec ^ { - 1 } \frac { \sqrt { x ^ { 2 } + 9 } } { x } \right)$$

A) $\frac { 3 } { x }$
B) $\frac { x \sqrt { x ^ { 2 } + 9 } } { x ^ { 2 } + 9 }$
C) $3 x$
D) $\frac { \sqrt { x ^ { 2 } + 3 } } { x ^ { 2 } + 3 }$