In “The Deadliest Tsunami in History,” the cause of the Indian Ocean tsunami was

a rupture in the Burma plate.
an unintended explosion in Japan.
a tornado off the coast of Sumatra.
mass animal migrations to the North.

a rupture in the Burma plate.

The cause of the Indian Ocean tsunami was a rupture in the Burma plate.

To find the cause of the Indian Ocean tsunami mentioned in the question, we need to analyze the given options:

1. A rupture in the Burma plate: A rupture in a tectonic plate could potentially result in a tsunami. However, there is no specific information provided about a rupture in the Burma plate being the cause of this particular tsunami.

2. An unintended explosion in Japan: An unintended explosion in Japan would not be directly linked to causing a tsunami in the Indian Ocean.

3. A tornado off the coast of Sumatra: Tornadoes are intense rotating windstorms that occur over land, and they are not typically associated with creating tsunamis. Therefore, it is unlikely that a tornado off the coast of Sumatra caused the Indian Ocean tsunami.

4. Mass animal migrations to the North: Mass animal migrations do not trigger tsunamis. Tsunamis are primarily caused by seismic activity, underwater earthquakes, volcanic eruptions, or landslides.

Based on the options provided, none of them accurately describe the cause of the Indian Ocean tsunami. The actual cause of the Indian Ocean tsunami, known as the 2004 Indian Ocean earthquake and tsunami, was a massive undersea earthquake with an epicenter off the western coast of northern Sumatra, Indonesia.