Name a three dimensional shape that cannot have a triangle as a two dimensional cross section.

A sphere

Step-by-step explanation:

A cross section of a three dimensional figure is the surface or intersection of the three dimensional figure and a plane, it is the shape obtained by cutting straight through the three dimensional figure

The shape of an inclined cross section of a cube can be a triangle however, he shape of a horizontal and inclined cross section of a sphere is a circle.