Correct Option
The correct option is 1 only
Explanation
The evolution of landscapes by running water is typically described through three stages of development: Youth, Mature, and Old. These stages reflect the changing dominance of vertical erosion, lateral erosion, and deposition as the river profile adjusts to the base level.
Statement-wise Analysis
- Statement 1 is Correct: In the youth stage, streams are relatively few and poorly integrated. They flow over the original slopes, creating shallow V-shaped valleys. Floodplains are generally absent or very narrow, and the stream divides are broad and flat with marshes or swamps.
- Statement 2 is Incorrect: Waterfalls and rapids are primary characteristics of the youth stage, where local relief is high and vertical erosion is dominant. In the mature stage, the river gradient reduces, vertical erosion decreases, and lateral erosion increases; consequently, waterfalls and rapids disappear.
- Statement 3 is Incorrect: In the old stage, the landscape is reduced to a low-lying plain (peneplain). The divides are broad and flat, not sharp or steep. Sharp and steep divides are characteristic of the youth and early mature stages, where dissection is active.
Key Takeaway
Key Takeaway: The Youth stage is defined by vertical erosion, V-shaped valleys, and waterfalls. The Mature stage is marked by lateral erosion and valley widening. The Old stage is characterized by deposition, broad flat divides, and the formation of a peneplain.