What coastal feature results from isostatic fall?

A coastal feature that results from isostatic fall is a raised beach. When an area of land experiences isostatic rebound, typically following the melting of glaciers, the land gradually rises, lifting the former wave-cut beach above the current sea level. This creates a raised beach, which is characterized by its flat, horizontal surface that is now positioned higher than the surrounding coastal areas, indicating where beaches once existed before the land rose.

In contrast, a wave-cut notch is a feature formed by the erosion of a cliff base by wave action, resulting in a small indentation. A knickpoint refers to a point of abrupt change in the profile of a river, often seen in river systems as they transition from one geomorphological region to another. A lagoon is a shallow body of water separated from the sea by a barrier, which does not relate to changes in land elevation due to isostatic processes. Therefore, the correct answer aligns with the process of isostatic rebound leading to the formation of features previously submerged by ocean waters.