TOEFL Listening: ETS-TOEFL听力机经 - 0P1O98S5TH5EX3D3P$

Why does the professor say this: A. To point out an apparent inconsistency with one of the proposed theories. B. To ask the students to think of an answer that is not presented in the textbook. C. To suggest an alternate theory about the cause of the Younger Dryas. D. To emphasize a point he made in a previous lecture.