What is the definition of usable water?

Usable water refers to water that can be utilized by living organisms, including plants, animals, and humans, for their survival and needs. It encompasses freshwater sources necessary for drinking, irrigation, sanitation, and various industrial applications, reflecting the essential role of water in sustaining life. This definition underscores the importance of water quality and availability, highlighting that usable water must be free from contaminants that would otherwise render it unsafe or unsuitable for these purposes.

The other options do not align with the definition of usable water. Water that is too polluted for any use would be unusable. Water that is only accessible to certain regions implies a limitation based on geography rather than quality or usability. Lastly, water exclusively found in oceans pertains to saline water, which is generally not usable for drinking or irrigation without desalination.