Question

which surface represents a plane in hyperbolic geometry?

Explanation:

In hyperbolic geometry, a plane is represented by a saddle - shaped surface. The first image is a sphere (not a hyperbolic plane), the second is a curved surface which resembles a saddle, the third is a flat - looking object but in hyperbolic geometry flat objects as we know in Euclidean geometry don't represent planes, and the fourth is a cube - like object which is also not a hyperbolic plane.

Answer:

The second surface (the saddle - shaped one)