California is one of the most seismically active regions in the world. Recently scientists published new calculations that reveal there is a 99.7 percent chance a magnitude 6.7 or larger earthquake will hit California in the next 30 years. Despite the new results, scientists still cannot predict exactly where in the state such an earthquake will occur or when.

Why are scientists so sure about their predictions concerning the future California earthquake?

ACalifornia has a long history of earthquakes.

BCalifornia lies on a rift zone that is gradually opening wider.

CCalifornia sits on top of two of Earth's major tectonic plates.

DCalifornia lies in the middle of two convergent tectonic plates.