Which boundary is formed by mountains, rivers, desert?

• A. Natural Boundaries
• B. Ethnic Boundaries
• C. Physical Boundaries
• D. Geometric Boundaries

Answer: (C)

Boundaries defined by the physical landscape are a classic example of physical boundaries. Mountains, rivers, and deserts create real, observable divides that influence how areas are defended, administered, and accessed. A mountain range can form a tough barrier, a river can serve as a natural line along which borders are drawn, and a desert can deter movement and settlement, all reinforcing separation between political units. Because the question highlights borders formed by these natural features, physical boundaries is the best fit. Ethnic boundaries describe divisions based on people and culture, while geometric boundaries are straight-line borders drawn on a map without regard to terrain.