What occurs at converging plate boundaries?

At converging plate boundaries, two tectonic plates move towards each other, which can lead to several geological processes. One significant occurrence at these boundaries is the formation of earthquakes due to the intense pressure and friction that builds up as the plates interact. When these stresses are released, it can result in seismic activity, causing earthquakes.

Additionally, converging plate boundaries often lead to mountain building. This occurs when one plate is forced beneath another, a process known as subduction, or when two continental plates collide and push against each other, causing the land to buckle and uplift, resulting in mountainous regions.

Thus, given that both the occurrence of earthquakes and mountain building are fundamental processes at converging plate boundaries, the option indicating both of these phenomena is the most accurate. Seafloor spreading does not occur at converging plate boundaries; instead, it is associated with divergent plate boundaries where tectonic plates move apart.