Which of the following nutrients provides the highest caloric value per gram?

Fat provides the highest caloric value per gram compared to carbohydrates, protein, and vitamins. Specifically, fat contains approximately 9 calories per gram, while carbohydrates and protein each provide about 4 calories per gram. Vitamins, in contrast, do not provide any calories since they are micronutrients essential for various body functions but do not serve as a direct energy source. This high caloric density of fat makes it a significant source of energy in the diet, especially in contexts where energy needs are high, such as during prolonged physical activity or in specific dietary regimes.