Answer:
D. Their patterns show that the Earth's magnetic field reverses every few hundred years, on average
Step-by-step explanation:
- The seafloor spreading is a process of the mid-oceanic ridges where the oceanic crust is formed by volcanic activity and it gradually moves on both sides of the ridges.
- The spreading takes place through the magma which are magnetized by the earth's magnetic field and spread in the direction of positive and negative properties.