Which description correctly captures the concept of nutrient density when comparing an apple and a candy bar?

Nutrient density refers to the amount of vitamins and minerals per calorie; an apple is more nutrient-dense than a candy bar because it provides more micronutrients and fiber per calorie.

Nutrient density is determined by sweetness and palatability; the candy bar is more nutrient-dense because it tastes better and thus has higher perceived nutrient value.

Nutrient density is the ratio of water to protein; fruits are always low nutrient density regardless of vitamin content because they contain high water proportions.

Nutrient density measures only carbohydrate content per serving; therefore, the candy bar is more nutrient-dense because it contains more grams of carbohydrate per serving than the apple.