Question

coral bleaching is a process in which corals lose their vibrant colors and turn completely white or pale due to the loss of their symbiotic algae, called zooxanthellae. these algae live inside the coral tissue and provide them with nutrients through photosynthesis, which is essential for the corals survival. however, when corals are stressed due to changes in their environment, they expel the algae, which leaves the coral without its main source of nutrients and causes it to turn white. coral bleaching can lead to the death of the coral if the stress is prolonged, and it can have serious impacts on the marine ecosystem as corals provide habitat and food for many other species. what is the primary cause of coral bleaching world - wide today? lower than expected ocean temperatures recreational fishing and boating activities increasing ocean temperatures due to global warming higher tides than normal

Explanation:

Coral bleaching occurs when corals are stressed due to environmental changes. Global warming leads to increasing ocean temperatures, which is a major stressor. Lower ocean temperatures (first option) are not a cause. Recreational fishing/boating (second option) and higher tides (fourth option) are not the primary global - wide cause compared to the large - scale impact of global - warming - induced ocean temperature increase.

Answer:

increasing ocean temperatures due to global warming