Dr. Greenhill wants to know how it is that some early adolescents come to make a connection between their personal lifestyle and environmental problems, while others don't. Furthermore, among those who see the connection, why do some become committed to environmentalism while others do not? Dr. Greenwald looks forward to probing the thoughts of young teens on these issues and trying to see the questions and issues through "14-year-old eyes." You recommend that Dr. Greenhill conduct a ________ study.