Which of the following is a common method for conserving water resources?

Rainwater harvesting is a highly effective method for conserving water resources as it involves the collection and storage of rainwater from surfaces like roofs, which can then be utilized for various purposes such as irrigation, potable uses, and groundwater recharge. This practice not only reduces the demand on traditional water sources but also helps in managing stormwater, reducing runoff, and minimizing erosion.

By capturing rainwater, communities and individuals can supplement their water supply, especially in regions prone to drought or with limited access to freshwater resources. Rainwater harvesting can be implemented at various scales, from small household systems to large community or municipal practices, making it a versatile solution for water conservation.

While other methods like desalination convert seawater to freshwater and drip irrigation provides efficient watering for crops, rainwater harvesting directly taps into a natural and renewable source while also promoting sustainable water management practices. Flood irrigation, on the other hand, is generally considered less efficient in water use compared to the other methods listed.