Which of the following is not an important reason why primatology has become increasingly important since the late 1950s? a. ​Behavioral studies have implications for understanding natural forces that have shaped human behavior. b. ​ Many nonhuman primates are threatened or seriously endangered. c. ​Through primatology we can better address the needs of primitive humans. d. ​The behavioral studies of any species provide a wealth of data on adaptation. e. ​Nonhuman primates are our closest living relatives.