What defines a watershed?

A watershed is defined as an area of land that drains into a specific body of water, such as a river, lake, or ocean. This definition is crucial because it emphasizes the entire landscape that contributes to the flow of water into a particular body through various paths, including streams, rivers, and groundwater. Understanding the concept of a watershed is essential for water management and environmental conservation, as it highlights the interconnectedness of ecosystems and the impact of human activities on water resources.

The other options do not accurately capture the essence of a watershed. A body of water surrounded by land refers to lakes or ponds, a structure for storing water pertains to reservoirs or tanks, and a water treatment facility is designed for purifying water for consumption. Each of these does not encompass the broader geological and hydrological concept of a watershed.