Final answer:
Seafloor spreading occurs at divergent boundaries and leads to the formation of mid-ocean ridges, deep ocean trenches, and volcanic arcs. Convergent boundaries and transform boundaries can also cause frequent earthquakes.
Step-by-step explanation:
Seafloor spreading occurs at divergent boundaries, where two tectonic plates move away from each other. This process results in the formation of mid-ocean ridges, which are underwater mountain ranges. The movement of the plates also leads to the formation of deep ocean trenches and volcanic arcs. When tectonic plates interact at convergent boundaries, earthquakes are more frequent. Transform boundaries, where plates slide past each other horizontally, can also result in frequent earthquakes.
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