TOEFL Reading: ETS-TOEFL阅读机经 - 7WB33334DL90DH38L$

According to paragraph 3, what do archaeologists want to know about the climate during the 40,000 years between around 75 kya and 35 kya A. Whether it was a reason that humans lived in caves B. Whether it was stable throughout that period C. Whether it changed in similar ways in Africa and in Europe D. Whether it was a factor in how the human cognitive process developed