Let $f ( x ) = x ^ { 4 } - 2 x ^ { 2 } + 1$

Multiple Choice

Let $f ( x ) = x ^ { 4 } - 2 x ^ { 2 } + 1$ on $[ - 2,2 ]$ Then the set of all c in (-2,2) guaranteed by Rolle's Theorem is

A) $\{ - 1 \}$
B) $\{ 0 \}$
C) $\{ 1 \}$
D) $\{ 0,1 \}$
E) $\{ - 1,0,1 \}$