**Core Concept**
Human milk and cow's milk have different compositions to meet the nutritional needs of infants and young children. Human milk contains a unique balance of nutrients, including proteins, fats, carbohydrates, vitamins, and minerals, which are essential for the growth and development of infants.

**Why the Correct Answer is Right**
Human milk contains more oligosaccharides compared to cow's milk. Oligosaccharides are complex carbohydrates that serve as a primary source of nutrition for the gut microbiota in infants. They also play a crucial role in the development of the infant's immune system. The oligosaccharides in human milk are not digestible by infants, but they are fermented by the gut microbiota, producing short-chain fatty acids that provide energy to the cells lining the colon and promote the growth of beneficial bacteria.

**Why Each Wrong Option is Incorrect**
* **Option A:** Human milk does not contain more lactose compared to cow's milk. Both human and cow's milk contain lactose as a primary source of carbohydrates, but the concentration is similar in both.
* **Option B:** Human milk does not contain more protein compared to cow's milk. While human milk contains a unique balance of proteins, the concentration is not significantly higher compared to cow's milk.
* **Option C:** Human milk does not contain more fat compared to cow's milk. While human milk contains a unique balance of fatty acids, the concentration is not significantly higher compared to cow's milk.

**Clinical Pearl / High-Yield Fact**
Human milk oligosaccharides (HMOs) are prebiotic fibers that promote the growth of beneficial bacteria in the infant's gut, supporting the development of a healthy gut microbiome.

**Correct Answer:** C. Oligosaccharides