Michael is studying the factors that affect corrosion of metals. He wants to test the effect that different concentrations of an acid will have on the corrosion of a metal. As he sets up and completes his experiment, which of the following experimental designs would be most likely to help him answer his question? A. Allow several metal samples to soak in different amounts of acid of a single concentration and then measure the amount of corrosion on each. B. Prepare solutions of different acid concentrations, measure 50 milliliters of each into different beakers, and place metal samples of different types but of the same mass into the beakers. C. After allowing several small metal sheets to be exposed to different acid concentrations, measure the surface area of each that is corroded. D. After allowing a small metal sheet to be exposed to one acid concentration, place it in different acid concentrations, then measure the surface area that is corroded.