A feature produced by water in desert areas is

A wadi is a feature produced by water in desert areas. A wadi is a valley, ravine, or channel that is dry for most of the year but carries water during occasional heavy rainstorms. The intermittent but sometimes torrential flow of water carves out these channels through erosion over time, creating distinctive dry valleys across desert landscapes.

Wadis are common in the Sahara Desert, the Arabian Desert, and other arid regions. They are important because they indicate the work of running water even in environments where water is scarce. After rain, wadis may fill rapidly and produce flash floods before drying out again.

The other options are all features produced by wind action, not water:

• Barchans are crescent-shaped sand dunes formed by wind deposition.
• Yardangs are elongated, streamlined ridges carved by wind abrasion.
• Zeugens are tabular rock formations where wind abrasion has eroded softer lower layers, leaving a harder caprock on top (mushroom-shaped rocks).