Which valley shape is produced through vertical erosion by rivers?

A V-shaped valley is produced through vertical erosion by rivers due to the process of downcutting. As a river flows, it erodes the land beneath it, cutting downward into the soil and rock. This erosion is most prominent in the upper reaches of rivers, where the gradient is steeper. The sides of the valley tend to be steep and narrow, resulting in the characteristic V-shape.

This shape is formed as the river deepens its channel while the valley walls are gradually worn away by weathering processes, including hydraulic action and abrasion. In contrast, other valley shapes, such as the U-shaped valley, are typically associated with glacial activity, where glaciers carve out broader, flatter valleys. Oxbow valleys are formed by river meandering and are not directly related to vertical erosion. Rift valleys are caused by tectonic activity and not by river actions.