Explanation: A tsunami is a series of large waves caused by a sudden displacement of water, often due to an earthquake or underwater landslide. The 2004 Indian Ocean tsunami was one of the deadliest natural disasters in recorded history, affecting several countries including India, particularly the city of Chennai.
The tsunami was triggered by a massive earthquake that occurred on December 26, 2004, off the coast of Sumatra, Indonesia. The earthquake had a magnitude of 9.1–9.3 on the Richter scale, making it one of the most powerful earthquakes ever recorded. The sudden movement of the tectonic plates caused a massive displacement of water, leading to the formation of a series of large waves that traveled across the Indian Ocean.
These waves reached the coast of Chennai and other parts of India, causing widespread destruction and loss of life. The tsunami waves were particularly devastating because they traveled at high speeds and had a significant height, reaching up to 30 meters in some areas. The waves engulfed coastal areas, destroying homes, infrastructure, and causing numerous casualties.
It is important to understand that while earthquakes are a common cause of tsunamis, other events such as underwater landslides or volcanic eruptions can also trigger them. The 2004 Indian Ocean tsunami highlighted the need for improved early warning systems and disaster preparedness measures to mitigate the impact of such events in the future.
In summary, the correct answer is (B) Tsunami, as the huge waves that engulfed many human lives in Chennai in December 2004 were caused by a tsunami triggered by a massive earthquake in the Indian Ocean. This event underscores the destructive power of natural disasters and the importance of understanding and preparing for such events.