Final answer:
An earthquake is most likely to occur at a site where two tectonic plates slide sideways past each other, such as at a transform boundary like the San Andreas Fault in California.
Step-by-step explanation:
An earthquake is most likely to occur at a site where two tectonic plates slide sideways past each other. This type of plate boundary is known as a transform boundary. When two plates slide past each other, they can get stuck due to friction. As stress builds up, the plates suddenly slip, causing an earthquake.
An example of a transform boundary where earthquakes occur is the San Andreas Fault in California. The Pacific Plate and the North American Plate are sliding past each other at this boundary, causing frequent earthquakes in the region.
Therefore, the answer to the question is Plate 3, as it represents a site where two plates are sliding sideways past each other, making it the most likely location for an earthquake.
Learn more about Plate tectonics