Which of the following is a form of coastal engineering aimed to help prevent erosion?

Rip-rap is indeed a form of coastal engineering designed to prevent erosion. It consists of large, loose rocks or concrete placed along shorelines, riverbanks, or slopes to absorb and deflect wave energy, thereby reducing the impact of waves on the shore and minimizing erosion. This method effectively stabilizes the shoreline by preventing the loss of sediment and protecting fragile coastal ecosystems.

While other options also serve as coastal engineering solutions aimed at erosion prevention, the focus on rip-rap specifically highlights its role as a material that directly mitigates the forces of water by utilizing its weight and shape to instigate natural sediment processes and coastal protection.

Jetties, groins, and breakwaters also contribute to erosion control, but they function through different mechanisms such as altering sand movement, redirecting water currents, or creating sheltered areas, which may indirectly affect erosion rates but do not provide the same direct sediment protection as rip-rap does.