Answer:
c. has been determined by radiometric dating
Step-by-step explanation:
- Radiometric dating is a method that is used to determined by the age of rocks as per the age of the oceanic crust the plates near the mid oceanic ridges are the most recent or new.
- The plates that are located farther away form there ridges are oldest and hence the age of the oceanic crust is not the same in all the places of the world oceans.