What is the role of a "Control Variable" in an experiment?

A control variable plays a crucial role in an experiment by remaining constant throughout the procedure. This consistency is vital because it ensures that any observed changes in the dependent variable can be attributed solely to the manipulation of the independent variable. By holding certain factors constant, researchers can eliminate alternative explanations for their results, thereby strengthening the validity of the experiment.

For instance, in an experiment testing the effect of sunlight on plant growth, variables such as the type of plant, the amount of water, soil type, and temperature should be controlled. By keeping these factors consistent, any increase or decrease in plant growth can be confidently linked to variations in sunlight exposure. In this way, control variables help maintain the integrity of the experiment and allow for accurate conclusions to be drawn from the data collected.