The level surfaces of the three functions f(x, y, z) listed below are either ellipsoids, paraboloids, hyperbolic paraboloids, planes, generalized cylinders, or cones. Match the non-trivial level surfaces of the functions with these names.

(a) f(x, y, z) = 2x − 3y + 5z
(b) f(x, y, z) = 4x2 + y2 − z
(c) f(x, y, z) = sqrt(x2+y2) - 5z