Which command is used to combine multiple surfaces into one?

• A. Union
• B. Paste surface
• C. Merge surfaces
• D. Solidify

Answer: (B)

In Civil 3D, the task of turning several independent surfaces into one seamless surface is about bringing their geometry together into a single surface object. The Paste Surface command does this by taking the data from one surface and pasting it into a target surface, effectively merging the areas covered by multiple surfaces into one cohesive surface. You can repeat the process with additional surfaces, pasting each into the same target to create a unified model, then manage boundaries or duplicates as needed. This fits the scenario because you’re assembling multiple surface definitions into a single dataset that represents the combined topography. The other options aren’t the same workflow: Union is a solids operation and doesn’t apply to surface data; Merge surfaces is a different concept that isn’t the standard method for consolidating multiple Civil 3D surfaces into one; and Solidify would convert into solids rather than preserving a continuous surface model.