Which of the following Edit Surface commands remove data from an existing surface?

• A. Delete Line
• B. Remove Vertex
• C. Trim Surface
• D. Delete Point

Answer: (D)

In Civil 3D, a surface is built from underlying data like points and breaklines, and the actual surface geometry is created from those inputs. To remove data from an existing surface, you target the data source itself rather than just altering the display or the mesh.

Deleting a data point directly removes that point from the surface’s data set, which forces the surface to recompute its triangulation and can remove triangles that depended on that point. This is the explicit way to remove data from the surface.

Other edit operations modify geometry or boundaries without removing a source data item. For example, removing a line or breakline, or trimming the surface, changes how the surface is defined or displayed but does not delete the underlying data point itself. Removing a vertex changes the mesh topology but leaves the source point data in place.

Thus, the command that truly removes data from an existing surface is deleting the point.