Which of the following best describes the primary purpose of a control group in a biology experiment?

• A. To guarantee that the hypothesis is correct
• B. To increase the number of variables being tested
• C. To provide a baseline for comparison with the experimental group
• D. To ensure that the experiment is repeated multiple times

Answer: (C)

Verified step by step guidance

1. Understand the purpose of a control group: A control group is used in experiments to serve as a baseline for comparison. It is not exposed to the experimental treatment or variable being tested, allowing researchers to isolate the effects of the independent variable.
2. Eliminate incorrect options: The purpose of a control group is not to guarantee the hypothesis is correct, as the hypothesis is a testable prediction that may or may not be supported by the results.
3. Eliminate another incorrect option: The control group does not increase the number of variables being tested. In fact, it helps to minimize variables by providing a consistent baseline.
4. Eliminate the final incorrect option: The control group does not ensure that the experiment is repeated multiple times. Repetition is a separate aspect of experimental design to ensure reliability.
5. Conclude the correct answer: The primary purpose of a control group is to provide a baseline for comparison with the experimental group, allowing researchers to determine the effect of the independent variable.