Let $f ( x ) = x ^ { 2 } + 2 x - 1$

Multiple Choice

Let $f ( x ) = x ^ { 2 } + 2 x - 1$ on $[ 0,1 ]$ . Then the set of all c in (0,1) guaranteed by the Mean Value Theorem is

A) $\left\{ \frac { 1 } { 4 } \right\}$
B) $\left\{ \frac { 1 } { 3 } \right\}$
C) $\left\{ \frac { 1 } { 2 } \right\}$
D) $\left\{ \frac { 2 } { 3 } \right\}$
E) $\left\{ \frac { 3 } { 4 } \right\}$