TOEFL Listening: ETS-TOEFL听力机经 - FWZYE5WN_E21Y93XP$

According to the professor, why is it often difficult for archaeologists to compare the shapes of vessels from different locations? A. The surface finish of a lot of pottery is in bad condition. B. Many ancient pots have never been drawn. C. Some archaeologists do not share the results of their work. D. Drawings of pottery do not always contain all the significant details.