Question

how do rivers become larger as they travel across land?
○ groundwater rises, adding water to rivers.
○ tributaries combine, adding water to rivers.
○ ice sheets melt slowly, adding water to rivers.
○ rainfall in an area increases, adding water to rivers.

Explanation:

Rivers grow in size as they travel primarily because smaller streams (tributaries) continuously flow into them along their path. While groundwater, melting ice, and rainfall can add water, the consistent, cumulative addition from tributaries is the main reason rivers become larger as they move across land.

Answer:

Tributaries combine, adding water to rivers.