Answer:
c. longshore currents
Explanation:
The main chemical process that is observed in the coasts is the one of dissolution, that is to say, the water of the sea is able in this case to dissolve the rocks, causing cavities or isolating fragments and conferring them peculiar structures.
The influence of living beings around the shape of the coast has been slow and continuous; For example, as they grow, the colonies that form coral reefs are forming great barriers that modify the coast.
The internal agents correspond to the characteristics of the structure of the rocks of the coast, such as their nature and degree of hardness, the abundance and size of loose materials, the depth of the sea in the vicinity of the shore.
Erosion of rocky shores caused by waves happens slowly, even in places where the rocks are relatively soft. The erosion rates per year on the cliffs are one meter, and represents approximately 5 percent of the erosion material that reaches the world's beaches.
In the modeling of the coast, the movement of sediments along the banks is also important. For example, the amount of beach sand that is transported on several coasts can reach a volume greater than one million cubic meters per year.
The main sources of beach and shore sediments are represented by rivers, which carry large amounts of sand to the ocean; the marine cliffs of unconsolidated material, which are worn by the waves, and the remains of biological origin, such as shells, coral fragments and other skeletons of small marine organisms. Wind-dragged sand can act as a source of sediment on the banks, although winds are generally more effective by removing sand from beaches than by depositing it.
