Concept:The starch test steps: boil the leaf in water, warm it in alcohol (ethanol) to remove chlorophyll, rinse, then add iodine solution.Explanation:Boiling in water kills the leaf cells, stopping enzyme action (so the starch is not changed) and breaking the cell membranes so iodine can later reach the starch.The chlorophyll is extracted by alcohol, not by boiling in water, and boiling does not isolate the starch. The leaf becomes soft, but that is not the purpose of the step.Answer:Option B (kill the leaf)