Answer:
D. carbohydrate, blue-purple
Step-by-step explanation:
Carbohydrates are one of many types of macronutrients found in certain foods and drink. For example, sugars, starches, and fibers are carbohydrates.
When starch is present, using an iodine solution will turn it blue-black or purple. If starch is NOT present, it will stay orange or yellow. The reason starch reacts with iodine is due to the amylose present in starch. Iodine is not soluble in water, so it's dissolved along with potassium iodide that forms a triiodide molecule. That then enters the helical structure of amylose and changes its color.