In the Study Conducted with Couples Viewing the Two Movies

Multiple Choice

In the study conducted with couples viewing the two movies, what is/are advantage(s) of nonparticipant observation?

A) pre-test and post-test observations help rule out 'selection' effects as the reason for post-test differences between groups attending the two movies
B) variables are those that can be observed without subjects' participation
C) the 'natural setting' of the treatment
D) all of these (a, b, c)