TOEFL Reading: ETS-TOEFL阅读机经 - 3NTAM84B9L6ZS8M1L$

According to paragraph 2, comparative behaviorists were interested in finding answers to all of the following questions EXCEPT A. How has animal behavior changed over time? B. How can emotions causing a specific behavior in one animal species help explain behavior in other animal species? C. To what degree can animal behavior be changed? D. How does the nervous system regulate animal behavior?