Which is one way that waves erode coastlines? O Back-and-forth movement loosens sediment and rock.
O Large rocks are picked up and deposited in new areas.
O Continuous impacts build up sediment and rock.
O Loose sediment is picked up and blown to other locations.

A.) back-and-forth movement loosens sediment and rock

Explanation:

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The back and forth movement erode the coastline

Let understand that "Coastline" is the area where the land meets the ocean. In some places, a coastline serves as beaches for entertainment.

In conclusion, the back and forth movement of the water continually loosens the sediment on the coastline till they get smoother and then eroded into the water.

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