Question

the topmost layer of the earth is made up of large pieces that fit together like a puzzle. however, these pieces don’t stay still, and sometimes they rub against each other. when these large sections of the earth’s crust, called tectonic plates, hit each other, they send vibrations through the surface of the earth. these vibrations are seismic waves. seismic waves are just like the ripples in a pond. but instead of traveling through water, they travel through the earth. when they reach the earth’s surface, they make the ground shake. that’s an earthquake. earthquakes are the result of a ripples traveling through water. b earth’s topmost layer sinking. c vibrations from seismic waves. d tectonic plates staying still.

Explanation:

The text states that when tectonic plates hit each other, they send seismic - wave vibrations through the Earth's surface, and when these vibrations reach the surface, they cause the ground to shake, which is an earthquake. So earthquakes are a result of these vibrations from seismic waves.

Answer:

C. vibrations from seismic waves.