Final answer:
The correct answer is A) Upwelling. Upwelling is a process where deep, nutrient-rich water rises to the surface due to prevailing winds pushing surface water offshore, promoting the growth of algae by providing essential nutrients.
Step-by-step explanation:
The movement of cold, nutrient-rich waters from the bottom of the ocean, promoting algae growth is called upwelling. This process occurs when prevailing winds blow along surface waters near a coastline, pushing the surface water offshore. This causes the deeper water, which is high in nutrients due to decomposing organisms, to rise to the surface and replace the displaced water. These nutrients are essential for the growth of algae and phytoplankton, which are vital to marine ecosystems as primary producers.
Eutrophication is an over-enrichment of water with nutrients, leading to excessive algae growth and potentially creating hypoxic conditions, but it is typically caused by runoff containing fertilizers and not by natural processes like upwelling. Therefore, ocean upwelling is the correct answer to the question about the movement of nutrient-rich waters promoting algae growth.