What is the process of desalination?

Desalination is specifically defined as the process of removing salt and other impurities from seawater to produce fresh water that can be used for drinking or irrigation. It involves various techniques, such as reverse osmosis or distillation, which effectively separate salts and minerals from the water. This process is crucial in areas where freshwater resources are scarce and is vital for ensuring a sustainable supply of drinking water.

The other choices represent different processes or concepts. The addition of minerals to water is related to water treatment but not to desalination. The treatment of water for agricultural use specifies a purpose of water treatment rather than the process of desalination itself. Lastly, filtering rainwater involves collecting and purifying natural precipitation, which is distinct from the process of desalination that specifically focuses on seawater.