Describe the 3-Space Graph of the Equation Z² = Y²

Describe the 3-space graph of the equation z² = y² + x².

A) a surface of revolution obtained by rotating the parabola z = x² in the xz-plane about the z-axis
B) a circular cone with vertex at the origin, axis along the z-axis, and semi-vertical angle
C) a circular cylinder with axis along the z-axis radius z
D) a circle having radius z in the xy-plane
E) a surface of revolution obtained by rotating the parabola z = y² in the yz-plane about the z-axis