Final answer:
Subduction zones on Earth offer clear evidence for the theory of plate tectonics, which describes the movement of lithospheric plates and the resulting geologic features.
Step-by-step explanation:
Subduction zones are areas on Earth where dense oceanic crust is forced beneath a lighter continental crust, leading to the formation of deep ocean trenches, high mountain ranges, and frequent seismic and volcanic activity. These geologic phenomena provide evidence for the theory of plate tectonics, which explains the movement of the Earth's lithospheric plates and the various interactions at their boundaries. The occurrence of subduction zones, along with other types of plate boundaries such as divergent (rift zones) and transform boundaries, illustrates the dynamic and continuous nature of the crustal rearrangement on our planet's surface.