Final answer:
Participants who take the ibuprofen are the experimental group, and those who take the placebo are the control group. The study is likely double-blind to control for the placebo effect and ensure differences are due to the treatment. The correct option is b) Experimental group; control group
Step-by-step explanation:
In the described study, participants who take the ibuprofen are the experimental group, and participants who take the placebo are the control group.
The researcher administers ibuprofen to test its effects on the pain of social exclusion, which forms the basis of the experimental group.
The placebo group is given a treatment that cannot influence the response variable, thus serving as the control to monitor potential effects due purely to participation in the study or due to the power of suggestion—a phenomenon often referred to as the placebo effect.
In a double-blind study, which is important to control for both experimenter and participant expectations, neither the researchers nor the participants know who is receiving the active treatment and who is receiving the placebo.
This setup helps to ensure that any observed differences between the two groups are likely a result of the treatment itself rather than other factors. The correct option is b) Experimental group; control group