Final answer:
Vitamins E, A, and C contribute to the antioxidant defense system, acting as scavengers for harmful by-products of metabolism known as free radicals. These vitamins play important roles in preventing cell and tissue damage.
Step-by-step explanation:
Vitamins E, A, and C contribute to the antioxidant defense system. These vitamins act as antioxidants by scavenging harmful by-products of metabolism known as free radicals, which can cause damage to cells and tissues. Vitamin E prevents fats from being oxidized, vitamin A helps keep cells differentiated, and vitamin C can block the action of initiators that damage DNA by oxidation.