Find the Derivative of the Function $$f ( x ) = \frac { 2 \sqrt { x } } { x ^ { 2 } + 9 }$$

Multiple Choice

Find the derivative of the function.
Select the correct answer.
$$f ( x ) = \frac { 2 \sqrt { x } } { x ^ { 2 } + 9 }$$

A)
$\frac { - 3 x ^ { 2 } + 9 } { \sqrt { x } \left( x ^ { 2 } + 9 \right) ^ { 2 } }$
B)
$\frac { 1 } { 2 x \sqrt { x } \left( x ^ { 2 } + 9 \right) }$
C)
$\frac { 1 } { 2 x \sqrt { x } }$
D)
$\frac { - 3 x ^ { 2 } + 9 } { \sqrt { x } \left( x ^ { 2 } + 9 \right) }$