Answer the following question given this paragraph: 

In arid regions, a mountain stream may flow onto flatter land. The stream comes to a stop rapidly. The deposits form an alluvial fan ( Figure below ).


Q: When a mountain stream flows onto flatter land and comes to a stop rapidly, what do the deposits form?

 Choices:

- conical fan

- vertical fan

- upstream fan

- alluvial fan

A:
alluvial fan
