Control variables are factors that researchers keep constant in an experiment to ensure that any changes in the outcome are due to the independent variable. For example, if a scientist is studying how different amounts of sunlight affect plant growth, they might control variables like soil type, water amount, and temperature. This way, they can be sure that the results are specifically related to sunlight exposure. By controlling these variables, researchers can draw clearer conclusions from their experiments. This practice helps eliminate confusion and ensures that the findings are reliable. In the plant growth example, controlling variables allows scientists to understand the true impact of sunlight on plant health.