TOEFL Reading: ETS-TOEFL阅读机经 - RY3J4H57PHA3C58VL$

According to paragraph 7, which of the following was true of human communities before 120,000 years ago? A. They obtained their raw materials from the area in which these materials were used. B. They left little in the way of archaeological evidence that can be used to understand their technologies. C. They were usually located less than 5 kilometers from other human communities. D. They stored raw materials at multiple locations.