Text 1: Geologist Park argues that the Earth's continents are slowly drifting at rates of a few centimeters per year. GPS measurements, seafloor magnetic stripes, and the matching geology of South America and Africa all confirm that what was once one supercontinent has fragmented over hundreds of millions of years.
Text 2: Geologist Singh agrees with the basic theory of plate tectonics but argues that "continental drift" oversimplifies the dynamics. It is the rigid plates of crust and upper mantle, not the "continents" themselves, that move; oceanic plates make up most of the moving system. Pop-science accounts that talk only of drifting continents, Singh argues, obscure the underlying mechanism.
Both authors would most likely agree that
- A
the continents are stationary.
- B
no measurements of plate motion exist.
- Ccheck_circle
Earth's outer layer moves over geological time.
- D
plate tectonic theory is incorrect.
Explanation
Both authors accept plate motion; they differ on terminology. A is shared. B, C, and D contradict both.