The parts that make up an assembly are called ________.

• A. Subassemblies
• B. Segments
• C. Modules
• D. Components

Answer: (A)

In corridor design, the parts that make up an assembly are subassemblies. An assembly acts as a cross-section template along an alignment and is built from multiple subassemblies, each modeling a specific portion of the roadway—such as a lane, shoulder, curb, ditch, or sidewalk. Each subassembly defines its own width, slope, and transitions, and combining them creates the full cross-section the corridor follows. Other terms like segments, modules, or components aren’t the standard building blocks for an assembly in Civil 3D, as they don’t specifically refer to the reusable cross-section pieces that compose an assembly. Subassemblies can come from a library or be created with Subassembly Composer, giving you the flexibility to build the exact cross-section you need.