TOEFL Listening: ETS-TOEFL听力机经 - DN2L52Y45JZLP2NMP$

Why does the professor say this: A. To acknowledge that she does not fully understand the relationship between the two organisms B. To ask students to explain what the disadvantages are for each organism C. To encourage the students to propose potential advantages of the relationship D. To indicate that the student overstated the disadvantage to the sea buttertfly