TOEFL Listening: ETS-TOEFL听力机经 - 1TEOE096NS9RQ5RVP$

Why does the professor mention satellite images? A. To describe how evidence of human settlement can be found in the desert. B. To point out that satellite images can sometimes be misinterpreted. C. To emphasize that very few people have ever lived in the Sahara. D. To disprove the claim that people always settled near water sources.