Which of the Following Is Not a Quadric Surface?
A) $x ^ { 2 } + z ^ { 2 } = 1$

Multiple Choice

Which of the following is not a quadric surface?

A) $x ^ { 2 } + z ^ { 2 } = 1$
B) $z = x ^ { 2 } + y ^ { 2 }$
C) $y = x ^ { 3 } + z$

D) $z = x ^ { 2 } - y ^ { 2 }$
E) $x ^ { 2 } + y ^ { 2 } + z ^ { 2 } = 1$