What term describes the land that receives water from a river and its tributaries?

• A. River terrace
• B. Floodplain
• C. Estuary
• D. River basin

Answer: (D)

Water that falls on a broad area eventually drains into the river and its feeder streams. The land that collects all that runoff and channels it toward the river and its tributaries forms the drainage basin, also called the river basin. It’s the whole area that contributes water to the river system, basically the river’s “catchment.” That’s why river basin is the best answer.

The floodplain is the low-lying area next to the river that often floods; it’s related to the river, but it’s about where flooding occurs, not the entire land that drains into the river. An estuary is the coastal zone where fresh water from the river mixes with seawater, not the drainage area. A river terrace is a landform left from the river’s old positions, not the land that collects and diverts water into the river.