TOEFL Listening: ETS-TOEFL听力机经 - 9WF9NO1J_QJ8M168P$

Why does the professor say this: A. To point out the redundancy in referring to the same substance in two ways B. To suggest that the topic of the lecture may be simpler than the students expect C. To highlight the comically scientific wording of his previous statement D. To simplify a concept that may have otherwise been too difficult to grasp