**Core Concept**
Human milk is a dynamic and nutrient-rich fluid that provides optimal nourishment to infants. The calorie content of human milk is crucial for the growth and development of the newborn. The calorie content of human milk varies throughout lactation, with the highest concentration found in colostrum.

**Why the Correct Answer is Right**
The calorie content of term human milk is approximately 67 kcal/100 ml. This value is essential for supporting the energy needs of the infant. Human milk contains a mixture of carbohydrates, proteins, and fats, which are broken down and utilized by the infant for growth and development. The lactose in human milk serves as the primary source of energy, while the fat content provides essential fatty acids. The protein content of human milk is also crucial for the development of the infant's tissues and organs.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because the calorie content of human milk is significantly higher than 50 kcal/100 ml, which would be insufficient for the energy needs of the infant.
* **Option B:** This option is incorrect because the calorie content of human milk is not as low as 30 kcal/100 ml, which would be inadequate for the growth and development of the infant.
* **Option D:** This option is incorrect because the calorie content of human milk is not as high as 80 kcal/100 ml, which would exceed the energy needs of the infant.

**Clinical Pearl / High-Yield Fact**
Human milk is a dynamic and nutrient-rich fluid that adapts to the changing needs of the infant throughout lactation. The calorie content of human milk is highest in colostrum and decreases over the first few days of life.

**Correct Answer:** C. 67 kcal/100 ml