What denotes a well-drained soil?

A well-drained soil is characterized by its ability to quickly absorb and transmit water, preventing the accumulation of excessive moisture on the surface. This is typically reflected in rapid water infiltration and minimal pooling, which allows for oxygen to reach plant roots and supports a healthy ecosystem. Well-drained soils often promote beneficial microbial activity and prevent waterlogging, which can adversely affect plant health.

In contrast, soils with high water retention and low microbial activity, significant clay content, or high organic matter and compactness may lead to conditions that are not conducive to drainage, resulting in poor aeration and potential damage to plants. Therefore, the defining feature of well-drained soil is its efficient water movement, as indicated in the correct answer.