What is an area of land that channels all the bodies of water within it to a common outflow point?

A: groundwater

B: river

C: watershed

D: leaching

C: watershed

The correct answer is C: watershed.

A watershed is an area of land that channels all the bodies of water within it to a common outflow point, such as rivers, streams, lakes, or oceans. It is often defined by the surrounding higher elevations, like mountains or hills, that separate it from other watersheds. The water within a watershed drains into the central outflow point, which could be a river or other body of water.

The correct answer is C: watershed.

A watershed is an area of land that channels all the bodies of water within it, such as rivers, streams, lakes, and even groundwater, to a common outflow point, such as a river mouth or an estuary. It is defined by the topography or the physical features of the land that determines how water flows across it.

To determine the correct answer to this question, you can first eliminate options A, B, and D based on their definitions:

- Option A, groundwater, refers to the water present underground in the soil or rock layers. While groundwater can contribute to the overall water flow within a watershed, it alone does not define a specific area of land that channels all bodies of water together.

- Option B, river, is a flowing body of water that usually follows a defined path. While rivers can be a part of a watershed, they are just one component of it and not the entire area that channels all water bodies.

- Option D, leaching, refers to the process of water dissolving and carrying away substances from the soil or rock layers. Leaching is not relevant to the concept of an area of land that channels all water bodies together.

By process of elimination, the correct answer is C: watershed. A watershed encompasses all the land and features that contribute to the flow of water within a specific area and directs it to a common outflow point.