Apharmaceutical company tests a new drug to relieve arthritis. some of the subjects receive a red capsule with the drug while others receive a red capsule with filler and no drug. those receiving the drug are called the group, while the subjects receiving the placebo are called the group.

experimental; control groups

Explanation:

The group receiving an experimental treatment is an experimental group.  The group is subject to modifications in the testing of the independent variable.

The independent variable attributes are registered as well as the outcome of the dependent variable.

A control group is a distinct group from the experiment so that the testing of  the independent variable can not affect the outcomes.  This separates the impacts on the experiment of the independent variable and  can help rule out possible explanations of the outcomes of the study.

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