Fact 1: Asandbar is formed by water moving sediment downstream.

Fact 2: Some sediment comes from natural erosion.

Given the two facts above, answer the question "A sandbar is formed by " with the following options: 
- loose soil
 - magma eruptions
 - wind currents
 - near the shoreline
 - seismic activity
 - natural erosion
 - flooding
 - Physical weathering


 

      natural erosion   