Answer:
We are given a '3-D figure with a curved surface'.
Now, we know that,
Polyhedron is a three dimensional figure having polygon faces.
Which means that the faces of the polyhedron are 2-D closed shapes bounded by straight lines.
Since, the 3-D figure consists of curved surface and the polyhedron does not have any curved surface.
Thus, we have,
A three-dimensional figure with a curved surface is not a polyhedron.