Answer:
A. Fertile soil
Explanation:
Landforms in the North European Plain include the extensive delta plain of The Netherlands that is formed by the deposits of the Rhine River as it enters the North Sea. Like many other delta plains, this area has rich and fertile soils and a flat terrain that is favourable for agriculture where it is properly drained. The Rhine has historically provided excellent transportation, and the region is one of the most densely populated areas in the world.
