Let $f ( x ) = x ^ { 2 } - 3 x \text { on } [ 0,3 ]$

Multiple Choice

Let $f ( x ) = x ^ { 2 } - 3 x \text { on } [ 0,3 ]$ on $[ 0,3 ]$ . Then the set of all c in (0,3) guaranteed by Rolle's Theorem is

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