The formation of layers in a material, with deeper layers denser than above.

• A. Density Stratified
• B. Density
• C. Convergent Plate Boundary
• D. Divergent Plate Boundary

Answer: (A)

Density stratification is the formation of layers in a material where deeper layers are denser than the ones above. Gravity pulls heavier material downward and lighter material upward, so the system arranges itself into stacked layers with increasing density as you go deeper. In seawater, differences in temperature and salinity create density variations, so the denser water sits below the less dense water, producing a stable, layered structure. This term directly describes the process of layering by density, making it the best choice. The word density describes a property rather than the action of forming layers, and plate boundary terms refer to tectonic processes, not layering by density.