Final answer:
The substance in question that offers cell protection, blood flow aid, and found in certain foods like fish is Vitamin E. As a fat-soluble antioxidant, Vitamin E helps neutralize harmful free radicals in the body.
Step-by-step explanation:
The substance that protects cells from damage, aids blood flow, and is found in fish, milk, egg yolks, spinach, fruits is Vitamin E. Hence, the correct option is D) Vitamin E. Vitamin E is a fat-soluble vitamin that plays a crucial role as an antioxidant in the body. Its antioxidant properties help protect cells against the damage caused by free radicals, which are harmful by-products of metabolism and environmental factors like radiation and pollution. Free radicals can lead to cell damage and contribute to the development of cardiovascular disease and cancer.
The properties of Vitamin E aiding blood flow and protecting cells align with the clues provided in the question. By contrast, Vitamin C is water-soluble and not typically associated with supporting blood flow, while Vitamins B2 and D have different primary functions unrelated to the benefits stated in the question. It's important to note that while Vitamins A, D, E, and K are fat-soluble and can accumulate in the body’s fat tissue, vitamins B and C are water-soluble and excess amounts are excreted in urine, not stored in the body.