What term describes all land that drains into a single body of water such as a lake or river?

• A. Drainage basin.
• B. Catchment.
• C. Watershed.
• D. Aquifer.

Answer: (C)

When we think about where rain and snowmelt go, the key idea is the land area that funnels all of that water to a single outlet. A watershed is that exact region—the land where all precipitation drains toward one specific body of water, like a lake or a river. The boundary of a watershed is set by the water divide, the high ground that steers water to different outlets. That makes watershed the best term for describing the whole contributing area to one water body.

Drainage basin and catchment are often used to describe the same concept, but watershed emphasizes the defined outlet and the divide that separates neighboring drainage areas. An aquifer, by contrast, is an underground layer that holds groundwater, not the surface drainage area, so it doesn’t fit this description.