Final answer:
Vitamin B12 is the nutrient that meets over 100% of the RDA in just 3oz of meat, making it essential for red blood cell formation, brain function, and DNA synthesis.
Step-by-step explanation:
When discussing which vitamin meets over 100% of RDA in only 3oz of meat, it's important to note that meat is a rich source of several vitamins, but not all of them will meet the entire Recommended Dietary Allowance (RDA) with such a small serving. Considering our options a) Vitamin A, b) Vitamin B12, c) Vitamin C, and d) Vitamin D, the answer is Vitamin B12. This nutrient is especially high in animal products, and a serving of 3oz of meat like beef or lamb can provide well over 100% of the RDA for an adult, ensuring adequate blood levels of this nutrient.
Vitamin B12 is essential for red blood cell formation, brain function, and DNA synthesis. Since it is a water-soluble vitamin and not stored in large amounts in the body, it is vital to consume B12 regularly, particularly for those who do not consume animal products. In the context of school subjects, this information is related to health and nutrition, which is part of biology.