Easy bruh
Answer:
D. Cooking a steak
Step-by-step explanation:
You see, cooking a steak is a chemical change. When you cook a steak on a grill lets say, chemical reactions take place which are irreversible. In other words, you can melt ice, you can mold the clay bcak to its original form, you can make a mixture dirty again, but you can't make a cooked stake raw again.