FINAL ANSWER:
D. is to the west of the Ural mountains.
Step-by-step explanation:
The correct answer is D because the Western Siberian Plain is indeed situated to the west of the Ural Mountains. The Ural Mountains are a natural boundary that separates the European part of Russia from the Asian part. This plain covers a vast area in the western part of Siberia, extending from the Ural Mountains to the Yenisei River and is characterized by its relatively flat terrain.
Options A, B, and C are not accurate descriptions of the Western Siberian Plain:
A. The largest flat plain in the world is the Amazon Basin, not the Western Siberian Plain.
B. The plain covers a significant portion of eastern Russia, but it also extends westward and is not limited to eastern Russia alone.
C. While the Western Siberian Plain does have a harsh climate, its population varies across the region, and there are areas with substantial human settlements and economic activities. The population is not uniformly low throughout the entire plain.