In which areas are Arenas soils predominantly found?

Arenas soils, characterized by their sandy texture, are predominantly found in coastal areas. The proximity to the ocean contributes to their formation as these soils are often a result of the weathering of marine sediments and the deposition of sandy materials by wind and waves. In coastal regions, the environmental conditions support the presence of these well-drained soils, which can be rich in minerals, making them suitable for certain types of agriculture and vegetation that can tolerate the sandy texture.

While the other options describe various landscapes where different types of soils may be found, they do not align with the specific characteristics and formation processes associated with Arenas soils. High-altitude mountains typically have rocky or clay soils, river valleys are often composed of alluvial soils rich in nutrients due to sediment deposits, and arid deserts generally feature dry, less fertile soils with minimal moisture retention. Therefore, the association of Arenas soils with coastal regions is well-supported by their unique formation conditions and environmental context.