The place where material is excavated when the zone of maximum stream velocity approaches the stream’s bed is called

The correct answer is A. scoured pools.

A scoured pool is a type of pool that forms when the zone of maximum stream velocity approaches the stream’s bed. This causes the stream to erode the bed, creating a depression. The depression fills with water, creating a pool.

B. riffles are areas of a stream where the water flows over a rough surface, causing the water to break into small waves.
C. oxbow lakes are crescent-shaped lakes that form when a meander in a river is cut off from the main channel.
D. flood plains are areas of land that are adjacent to a river or stream and that are prone to flooding.