The earthquake and tsunami that occurred in the Indian Ocean once again allowed human beings to appreciate the power of nature. Although there are many strings of islands in the periphery of China's sea area, surrounded by reefs, forming a natural barrier against the tsunami, we still have to live in peace. It is far away from the coast. Sometimes an earthquake in the deep sea does not directly cause damage to our country, but the tsunami caused by the earthquake can cause huge damage. The tsunami wave can propagate in the ocean for a long distance at a speed of 800 kilometers per hour, forming tens of meters. High surge. What is the main argument supported by this passage? ['Earthquake and tsunami warn the world for the deep ocean.', 'Earthquake and tsunami in the Indian Ocean warns of deeper ocean research in China.', 'Tsunami caused by earthquake can cause huge damage.', 'Natural disasters are brutal.']