What is a common use of gabions in stream bank stabilization?

Gabions are commonly used in stream bank stabilization primarily because they provide a structural solution that helps prevent erosion and collapse of banks. By utilizing wire mesh filled with rocks or other materials, gabions can resist the force of water flow and the weight of the soil above, effectively stabilizing the bank. This method is especially beneficial in scenarios where the immediate establishment of vegetation may not be feasible, allowing the soil to remain intact even in the absence of plant roots.

While options discussing enhancing natural vegetation growth, supporting structural integrity of steps, or improving water clarity relate to specific aspects of ecological or structural design, they do not specifically address the primary function of gabions in the context of stabilizing stream banks. The key advantage of using gabions lies in their capacity to provide stability and support to the bank structure, making option C the most fitting answer.