Find $\lim _ { h \rightarrow 0 } \frac { f ( x + h ) - f ( x ) } { h }$

Multiple Choice

Find
$\lim _ { h \rightarrow 0 } \frac { f ( x + h ) - f ( x ) } { h }$ for $f ( x ) = 4 - 6 x$ .

A) 6
B) 10
C) $- 6$
D) 4
E) limit does not exist