A watershed, or drainage basin, is a region of land where rain or snow drains downhill into a body of water, such as a river, lake, sea, ocean or wetland. The water in drainage basins is most likely used
A.
by plants and animals as a source of water.
B.
in developed areas for irrigation and cooking.
C.
by humans for drinking and bathing.
D.
in large cities for plumbing and sewage.