What is a tributary?

A tributary is defined as a smaller river or stream that flows into a larger river. This relationship is significant in river systems as tributaries contribute additional water, sediment, and nutrients to the larger river, thus affecting its flow and ecosystem. Understanding tributaries is essential for comprehending river dynamics, watersheds, and the overall drainage patterns in a landscape.

The other options describe different aspects of water bodies. For instance, a large river that flows into an ocean refers to a river's ultimate destination, while a natural body of water where rivers meet indicates confluences or deltas but does not capture the concept of a tributary specifically. An artificial water channel would suggest human-made structures that do not fit the definition of natural tributaries.