The passage suggests which of the following about the relationship between the theory of plate tectonics and Morgan's suggestion? A. Morgan's suggestion indirectly helped to discredit certain aspects of the theory of drifting tectonic plates. B. Morgan's suggestion assumes that the theory of drifting tectonic plates is correct. C. Evidence that contradicts Morgan's suggestion must also, by virtue of that fact, contradict the theory of drifting tectonic plates.