Find $\frac { f ( x + h ) - f ( x ) } { h }$

Multiple Choice

Find $\frac { f ( x + h ) - f ( x ) } { h }$ for the given function.
- $$f ( x ) = x ^ { 2 } + 8 x$$

A) 1
B) $2 x + h + 8$
C) $2 x + 8$
D) $2 x h + h ^ { 2 } + 8$