Using the control group concept, it is found that the correct option is:
- The group that received a pill pack resembling the new weight-loss pill pack (the placebo pack) is the control group.
What are control groups and treatment groups?
- In an experiment, the control group is the one that receives no treatment, or the standard treatment/placebo.
- The treatment group is the one that receives the new/different treatment.
In this problem:
- One group received a placebo.
- The other group received a new weight-loss pill.
Hence, applying the concept, the group that received a pill pack resembling the new weight-loss pill pack (the placebo pack) is the control group.
You can learn more about control and treatment groups at https://brainly.com/question/1425784