A graphical depiction of the vertical alignment of a roadway.

• A. Elevation
• B. Plan
• C. Profile
• D. Section

Answer: (C)

The question is about how the road’s height changes along its path. The vertical geometry, or how elevation varies along the route, is shown in a profile. A profile plots elevation of the centerline against distance along the alignment, revealing grades (slopes) and vertical curves that create the road’s crest and sag sections. This longitudinal view is what engineers use to assess sight distance, drainage, and ride quality as you move along the road.

In contrast, a plan is a top-down view of the road’s horizontal path, showing alignment left and right from above; a cross-section (section) is taken perpendicular to the centerline to show the roadway width and typical lane/ditch features at a single station. Elevation on its own refers to the height of a point and doesn’t convey how elevation changes along the route. So the correct depiction of the vertical alignment is the profile.