Final answer:
The vast majority of large tsunamis are generated in the Pacific Ocean due to the high level of seismic activity in the region.
Step-by-step explanation:
A vast majority of all large tsunami are generated in the Pacific Ocean. Tsunamis are typically caused by underwater earthquakes, landslides, or volcanic eruptions. The Pacific Ocean is known for having a high level of seismic activity, particularly along the tectonic plate boundaries, which makes it more prone to tsunamis.