Propose an experiment (brief outline) to test how pH affects salivary amylase activity using starch substrate, indicating expected results and controls.

• A. Outline: incubate starch with bacterial cultures at varying pH and attribute changes in starch breakdown solely to human salivary amylase, which confounds microbial activity with human enzyme effects.
• B. Outline: incubate equal amounts of salivary amylase with starch at several pH values (e.g., pH 3, 5, 7, 8), measure reducing sugar production over time, include no-enzyme control and heat-inactivated enzyme control; expect maximal activity near neutral pH and minimal activity at low pH (pH 3), demonstrating pH sensitivity.
• C. Outline: incubate saliva samples only at pH 2 and immediately run them on a lipid panel to detect triglyceride changes as a proxy for amylase activity, a design that uses unrelated outcome measures and insufficient pH range.
• D. Outline: feed volunteers different beverages in the clinic and ask them to subjectively rate taste changes to infer salivary amylase pH activity without biochemical measures, a nonquantitative and indirect approach that will not test enzyme kinetics.

Answer: (B)