Which is not a cause of beach erosion

Question

Human activity like building too close to the shoreline and damaging sand dunes
Wave action the continuous movement of water
Beach renourishment strategies like building up sand dunes and supporting them with fence
Storm waves can move sand deeper into the water creating sand bars

Answer 1

The option that is not a cause of beach erosion is:

Beach renourishment strategies like building up sand dunes and supporting them with fences.

Beach renourishment is actually a method used to prevent or mitigate beach erosion by adding sand to the beach or reinforcing sand dunes. The other options (human activity, wave action, and storm waves) are indeed causes of beach erosion.