TOEFL Listening: ETS-TOEFL听力机经 - VT441943ZW98MIQDP$

Why does the professor say this? A. She wants the student to stay focused on her question. B. She knows that the students are near solving her question. C. She is not sure if the student understands what an alpha is. D. She is more interested in the alpha than the suggestions made by other students.