Final answer:
An earthquake is a sudden release of energy in the Earth's crust caused by tectonic movement.
Step-by-step explanation:
An earthquake is a natural event characterized by the sudden release of energy in the Earth's crust. This occurs due to tectonic movement, which refers to the shifting and fracturing of Earth's lithosphere. When stress builds up along fault lines, it is released in the form of seismic waves, resulting in an earthquake. A volcanic eruption, on the other hand, is a different natural event that occurs when molten rock, ash, and gases are ejected from a volcano.
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