Which bridge type is often supported with trusses and is among the oldest types of modern bridges?

• A. Cantilever Bridge
• B. Suspension Bridge
• C. Truss Bridge
• D. Arch Bridge

Answer: (C)

Truss-based designs rely on a network of triangles that efficiently carry and distribute loads, placing all the forces into the supports through a rigid framework. A bridge that uses this lattice of triangles is described as being supported with trusses, because the truss system is its primary load-carrying structure. Historically, such truss configurations were among the first practical ways to span larger gaps with available materials (timber and early iron/steel), making them one of the oldest modern bridge types. Other bridge types transfer loads in different ways—for example, suspension relies on cables, and arch bridges transfer load through an arch action—so they aren’t described by having a truss framework as their defining support.