Which of the following is NOT a type of irrigation system?

Wind irrigation is not recognized as a legitimate type of irrigation system. The other methods listed—surface, drip, and sprinkler irrigation—are widely used and established techniques for distributing water to crops.

Surface irrigation involves the distribution of water over the soil surface by gravity, allowing it to flow through furrows or basins. Drip irrigation uses a system of tubes and emitters to deliver water directly to the plant roots, which minimizes water loss and conserves resources. Sprinkler irrigation mimics natural rainfall by spraying water over the plants, ensuring even coverage.

In contrast, the term "wind irrigation" does not correspond to any established method of applying water in agricultural practices. Wind can influence the effectiveness of irrigation systems (e.g., in how water evaporates or is distributed), but it does not represent a defined approach to irrigation itself.