Answer:
C. Principle of original horizontality
Explanation:
The Law of Original Horizontality suggests that all rock layers are originally laid down (deposited) horizontally and can later be deformed. This allows us to infer that something must have happened to the rocks to make them tilted.
West Siberian Plain, Russian Zapadno-sibirskaya Ravnina, one of the world's largest regions of continuous flatland, central Russia. It occupies an area of nearly 1,200,000 square miles (3,000,000 square km) between the Ural Mountains in the west and the Yenisey River valley in the east.