The student clearly states the independent variable as the pH levels of the reaction medium and the dependent variable as the catalytic activity of pepsin on gluten, measured by absorbance. The methodology is well-detailed, allowing for reproducibility, and includes a clear explanation of controlled variables and safety, ethical, and environmental considerations. However, the student needs to provide more clarity on the techniques used for measuring pH and absorbance, as well as justify the choice of pH levels and the number of trials conducted. Overall, while the methodology is organized and coherent, addressing these gaps will strengthen the investigation.
