TOEFL Listening: TPO-TOEFL听力TPO - B1507Y1EVTCBAZ57R$

Why does the man assume that the woman is in Professor Simpson's class? A. The man recently saw the woman talking with Professor Simpson. B. The woman mentioned Professor Simpson's name. C. The woman is carrying the textbook used in Professor Simpson's class. D. The woman is researching a subject that Professor Simpson specializes in.