A rejuvenated topography is characterized by:
(a) River terraces
(b) Incised Meanders
(c) Structural benches
(d) Knick-Points
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Question

A rejuvenated topography is characterized by: 
(a) River terraces 
(b) Incised Meanders 
(c) Structural benches 
(d) Knick-Points
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Accepted Answer

A rejuvenated topography, resulting from uplift or a drop in sea level, leads to renewed downcutting by rivers. Here's why Option 2, (a), (b) and (d), is the correct answer and why the others are incorrect:

*   **(a) River terraces:** River terraces are remnants of former floodplains that are left at higher elevations as the river cuts down into its valley. This downcutting is a direct result of rejuvenation, making river terraces a key characteristic of a rejuvenated landscape. The river is essentially re-working its valley, leaving behind evidence of its previous levels.

*   **(b) Incised Meanders:** Incised meanders are meanders that have been cut deeply into the bedrock. This occurs when a river that was previously meandering on a floodplain experiences rejuvenation. The river's increased erosive power allows it to cut vertically into the existing meander pattern, forming deep, entrenched meanders. This is a classic feature of rejuvenated topography.

*   **(d) Knick-Points:** Knick-points (or nick points) are abrupt changes in a river's gradient, often appearing as waterfalls or rapids. They represent a point where the river's erosive power is concentrated. Rejuvenation often creates or exposes knick-points as the river adjusts to the new base level and erodes upstream.

Now, let's explain why the other options are incorrect:

*   **Option 1: (a), (b), (c) and (d):** While (a), (b), and (d) are correct, (c) Structural benches are not directly related to rejuvenation. Structural benches are formed due to differential erosion of alternating layers of resistant and less resistant rock. While rejuvenation *could* expose existing structural benches, they are not a *result* of the rejuvenation process itself. They are pre-existing features that might be highlighted by renewed erosion.

*   **Option 3: (b), (c) and (d):** As explained above, structural benches (c) are not a direct result of rejuvenation. River terraces (a) are a key indicator of rejuvenation, making this option incorrect.

*   **Option 4: (c) and (d):** Again, structural benches (c) are not a direct result of rejuvenation. River terraces (a) and incised meanders (b) are both important features of a rejuvenated landscape, making this option incomplete and therefore incorrect.

Therefore, Option 2, (a), (b) and (d), is the most accurate answer because river terraces, incised meanders, and knick-points are all direct results and characteristic features of a rejuvenated topography.