Internal Redundancy is described as:

• A. Continuity of load path from span to span.
• B. If one member were to fail, load would be redistributed to other members and bridge failure would not occur.
• C. The three main components of a bridge.
• D. Creation of multiple load paths by elements that are mechanically fastened together.

Answer: (D)

Internal redundancy is about having more than one load path inside the bridge so forces can flow through several members. This resilience comes from connecting members with fasteners to create a network of paths, so if one member loses load-carrying capacity, the others share the load and the structure remains capable of carrying it. The option that describes multiple load paths created by mechanically fastened elements captures this idea precisely, because it emphasizes both alternate routes for forces and how they’re joined. The other statements describe different concepts: continuity from span to span focuses on the overall path rather than multiple routes; identifying the main components is about classification, not load sharing; and while redistribution of load is a consequence of redundancy, saying it would never fail is too absolute and misses the emphasis on alternate load paths formed through connections.