What is an earthquake?

An earthquake is defined as the vibration of Earth produced by the rapid release of energy, typically due to the movement of tectonic plates along faults. When stress builds up in the Earth's crust, it can suddenly release this energy, resulting in seismic waves that cause the ground to shake. This process is intrinsic to the geology of our planet, where the movement of tectonic plates can lead to both small tremors and significant seismic events.

The other options do not accurately describe an earthquake. Describing an earthquake as a natural disaster caused by flooding overlooks the geological and seismic processes involved. The idea of tectonic plate movement solely causing land erosion is overly simplistic and does not encompass the full scope of tectonic activity, which is fundamentally about energy release and vibrations. Lastly, stating that earthquakes only affect oceans misrepresents the phenomenon's impact, as they can occur on land and affect various regions, not just marine environments.