What does rainwater harvesting involve?

Rainwater harvesting involves collecting and storing rainwater for various uses, such as irrigation, drinking, or household activities. This practice captures rainwater runoff from roofs and other surfaces, directing it to storage systems like tanks or cisterns. The significance of rainwater harvesting lies in its ability to provide a sustainable source of water, particularly in areas where water scarcity is a concern. It also helps in reducing runoff, which can lead to soil erosion and water pollution.

The other options describe different water management practices. The transfer of water from rivers, filtering groundwater, and pumping water from lakes each pertain to conventional methods of sourcing water rather than the process of specifically harvesting rainwater. Thus, the correct answer accurately captures the essence of what rainwater harvesting entails.