Concept:Volcanic features are landforms created by volcanic activity, while ventifacts are formed by wind erosion.Explanation:A caldera is a large volcanic crater formed by collapse after an eruption.A geyser is a hot spring that erupts water and steam due to volcanic heat.A dyke is an intrusive volcanic feature formed when magma cuts across rock layers.A ventifact is a rock shaped and polished by wind-blown sand, not by volcanic activity.Answer:D. Ventifact