Final answer:
A 2-dimensional cross section of a 3-dimensional object represents a slice of the object taken along a particular plane.
Step-by-step explanation:
A 2-dimensional cross section of a 3-dimensional object represents a slice of the object taken along a particular plane. It is like cutting through the object at a specific angle and observing what the cut looks like. For example, if you cut a cylinder horizontally, the cross section would be a circle. If you cut it vertically, the cross section would be a rectangle.