Which of the following demographic groups seems to be having difficulties with marital satisfaction in recent years?

Psychophysics is a branch of psychology that studies

a. the relationship between the disciplines of physics and psychology b. the brain as a physical object c. the relation between a physical stimulus and the sensory experience it ultimately gives rise to d. the role of the autonomic nervous system e. the physical basis of motivation, emotion, and other mental activity

Each of the following is identified by the communication model of persuasion as a key element in changing people's behaviors EXCEPT ______

a. the source b. the medium of communication c. characteristics of the audience d. the context