The correct option is (c).
Explanation
Fold mountains are classified based on their geological age into Young Fold Mountains and Old Fold Mountains. This classification determines their physical characteristics, such as height, slope, and peak shape, primarily due to the duration of exposure to erosional forces.
Statement-wise Analysis:
- Statement 1 is Incorrect. Both the Ural Mountains (Russia) and the Appalachians (North America) are Old Fold Mountains. They were formed hundreds of millions of years ago (during the Paleozoic era). In contrast, Young Fold Mountains, such as the Himalayas, Alps, and Andes, were formed much more recently during the Tertiary period.
- Statement 2 is Correct. Because these mountain ranges are geologically old, they have been subjected to denudation and erosion by exogenic forces (wind, water, glaciers) for a very long period. This prolonged erosion has worn down sharp, conical peaks, resulting in rounded features.
- Statement 3 is Correct. The continuous process of erosion over millions of years has significantly reduced the vertical height of these ranges. Consequently, Old Fold Mountains generally exhibit lower elevations compared to the towering heights of Young Fold Mountains.
Key Takeaway:
Old Fold Mountains (e.g., Aravallis, Urals, Appalachians) are characterized by low elevations and rounded peaks due to extensive erosion, whereas Young Fold Mountains (e.g., Himalayas, Andes) feature high elevations and sharp, rugged peaks.