Which characteristic of coastal dynamics limits the abundance of aquatic organisms?

consistent water depth levels
consistent water temperatures
varied tidal action
varied water salinity

The correct answer is "Varied tidal action".

Explanation:

Varied tidal action refers to the presence of tides with different sizes and forces along a coast. This coastal dynamics characteristic limits the abundance of aquatic organisms because organisms must survive tidal action. Varied tidal action interferes with the adaptation of the aquatic organisms, as only a few organisms can survive this characteristic such as sea stars, sea urchins and sea cucumbers.