**Core Concept**
Vitamin K deficiency is a critical concern in newborns, particularly those born to mothers who do not receive adequate Vitamin K prophylaxis during pregnancy or delivery. Human milk contains a lower concentration of Vitamin K compared to formula, but it is generally sufficient for the newborn's needs. However, human milk-fed babies are less likely to develop Vitamin K deficiency due to the presence of other nutrients and the gut microbiota that support Vitamin K production.

**Why the Correct Answer is Right**
Vitamin K deficiency in newborns is primarily related to the lack of adequate Vitamin K prophylaxis, which is more commonly associated with formula-fed babies. Human milk contains a lower concentration of Vitamin K, but it is generally sufficient for the newborn's needs. In addition, human milk-fed babies have a unique gut microbiota that supports Vitamin K production, which reduces the risk of deficiency.

**Why Each Wrong Option is Incorrect**
**Option A:** Necrotizing enterocolitis is a known complication of formula-fed babies, particularly those born prematurely. This condition is more common in formula-fed babies due to the absence of beneficial gut microbiota and the presence of undigested lactose, which can lead to inflammation and tissue damage.

**Option B:** Otitis media is a common complication of formula-fed babies, particularly those exposed to tobacco smoke or with a family history of allergies. Formula-fed babies are at a higher risk of developing otitis media due to the alteration of the gut microbiota and the presence of undigested lactose, which can lead to inflammation and infection.

**Option C:** Hypocalcemia is a known complication of human milk-fed babies, particularly those born to mothers with a history of hyperparathyroidism or those with a family history of hypocalcemia. Human milk contains a lower concentration of calcium compared to formula, which can lead to hypocalcemia in vulnerable newborns.

**Clinical Pearl / High-Yield Fact**
Human milk-fed babies have a unique gut microbiota that supports Vitamin K production, which reduces the risk of deficiency. However, human milk-fed babies are at a higher risk of developing hypocalcemia due to the lower concentration of calcium in human milk.

**Correct Answer Line**
✓ Correct Answer: D. Vit K deficiency