Answer:
The cross-section that is obtained by this slicing is:
Hyperbola.
Explanation:
If a double cone is intersected by a vertical plane passing through the point where the tips of the cones meet then the shape of the cross-section that is obtained by this slicing will be a hyperbola.
( Since the plane cuts both the sections of the cone and hence we will get a curve on both the cones opening in the opposite direction and hence such a figure that is obtained is called a hyperbola)