The correct option is A-4, B-3, C-1, D-2
Explanation
Mountains are classified based on their mode of formation (orogeny) and geological age. The primary classifications include Fold Mountains (subdivided into Young and Old based on age), Block Mountains formed by faulting, and Volcanic Mountains formed by the accumulation of volcanic material.
Detailed Analysis:
- A. Rhine Valley (Block Mountain): The Rhine Valley is a classic example of a rift valley (graben) formed by tensional forces in the Earth's crust. It is bordered by Block Mountains (horsts), specifically the Vosges Mountains in France and the Black Forest in Germany. In the context of this classification, it represents the fault-block landform system.
- B. Appalachians (Old Fold Mountain): The Appalachian Mountains in North America are Old Fold Mountains. They were formed during the Paleozoic era (approximately 480 million years ago). Due to their age, they have undergone significant denudation, resulting in lower elevations and rounded peaks compared to younger mountain ranges.
- C. Fujiyama (Volcanic Mountain): Mount Fuji (Fujiyama) in Japan is a prominent Volcanic Mountain. It is a stratovolcano formed by the accumulation of lava, ash, and other volcanic debris ejected during eruptions over thousands of years.
- D. Himalayas (Young Fold Mountain): The Himalayas are Young Fold Mountains formed during the Cenozoic era (Tertiary period) due to the collision between the Indian and Eurasian tectonic plates. They are characterized by high, rugged peaks, deep valleys, and ongoing tectonic activity.
Key Takeaway:
Young Fold Mountains (e.g., Himalayas, Alps, Andes) are geologically recent with high peaks; Old Fold Mountains (e.g., Appalachians, Urals, Aravallis) are ancient and eroded; Block Mountains (e.g., Black Forest) result from faulting; and Volcanic Mountains (e.g., Mt. Fuji, Mt. Kilimanjaro) are built by volcanic eruptions.