This GED Practice Test science question comes from the Scientific Reasoning section of our GED Online Course. This science lesson breaks down how to design an experiment and the scientific method.
The correct answer is (C) Establishes a baseline measure to compare dependent variables to. A control group functions as a baseline measure or constant that is not influenced by experimental manipulations. It does not receive treatment in a study. Controls are used for comparisons.
One type of control is a placebo. This false treatment is administered to a control group to account for the placebo effect. This is a psychological effect where the brain convinces the body that a fake treatment is the real thing. Often, experimental drug studies use placebos.
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