Some possible signs of an upcoming earthquake include the ground tilting, the water levels in wells changing, and minor tremors called foreshocks. What can be said about these events?
Select one:

These events do not happen in all earthquakes and are not reliable indicators.

These events do not happen. They are folk stories. There are no indicators of earthquakes.

These events happen before every earthquake. They allow us to reliably predict earthquakes.

At least one of these events always happens before an earthquake. They are reliable indicators.