The correct answer for the Question is C. Glacial melting. It is not caused by human events but occurs when glaciers located at high altitude start to melt. Glaciers are large sheets of snow and ice that are found on land all year long. They are found in the Western United States, Alaska, the mountains of Europe and Asia, and many other parts of the world. Warmer temperatures cause glaciers to melt faster than they can accumulate new snow. Therefore, this is not caused by human events.