GRE Reading Comprehension: PPO-GRE阅读PPO - JOP6U3X4RBJDB5U4R

Which of the following best describes the function of the highlighted sentence? A. It points out some unintended consequences of a theory. B. It elucidates the thinking behind Morgan's suggestion. C. It explains why the theory of plate tectonics had been accepted. D. It expresses the author's attitude toward Morgan's suggestion. E. It introduces an alternative to Morgan's suggested explanation.