TOEFL Listening: ETS-TOEFL听力机经 - W34733PA35GCO64LP$

What is the lecture mainly about? A. The distribution of early agricultural methods from New Guinea to other countries. B. Various types of crops grown in early centers of agriculture. C. Evidence supporting the theory that agriculture developed independently in New Guinea. D. Advanced techniques used by archaeologists to identify farming methods in the earliest centers of agriculture.