Find the Derivative of the Function $f ( x ) = - 3 x + 2$

Find the derivative of the function. $f ( x ) = - 3 x + 2$

A) $2$
B) $\frac { 1 } { 3 }$
C) $- 3$
D) $- \frac { 1 } { 3 }$
E) $3 x$