**Core Concept**
Breastfeeding jaundice is a condition that affects newborns, typically occurring within the first week of life. It is characterized by an elevated bilirubin level, leading to jaundice. The exact cause of breastfeeding jaundice is not entirely understood, but it is believed to be related to the frequency and efficiency of milk removal from the breast, as well as the composition of the breast milk.

**Why the Correct Answer is Right**
Breastfeeding jaundice is not caused by the bilirubin content of the breast milk, but rather by the frequency and efficiency of milk removal from the breast. This is in contrast to breast milk jaundice, which is caused by substances in the breast milk that can increase bilirubin levels. The condition is often associated with dehydration, inadequate milk intake, and poor maternal-infant bonding.

**Why Each Wrong Option is Incorrect**
**Option A:** Breastfeeding jaundice is caused by the bilirubin content of the breast milk. *This is incorrect because breastfeeding jaundice is not caused by the bilirubin content of the breast milk, but rather by the frequency and efficiency of milk removal from the breast.*

**Option B:** Breastfeeding jaundice is a common condition that affects 50% of newborns. *This is incorrect because breastfeeding jaundice is relatively rare, affecting only a small percentage of newborns.*

**Option C:** Breast milk jaundice is the same as breastfeeding jaundice. *This is incorrect because breast milk jaundice and breastfeeding jaundice are two distinct conditions with different causes and mechanisms.*

**Option D:** Breastfeeding jaundice can be treated with phototherapy. *This is incorrect because breast milk jaundice can be treated with phototherapy, but breastfeeding jaundice is often treated by ensuring adequate milk intake and improving maternal-infant bonding.*

**Clinical Pearl / High-Yield Fact**
It's essential to differentiate between breastfeeding jaundice and breast milk jaundice, as their causes and treatments differ. Breastfeeding jaundice is often associated with dehydration and inadequate milk intake, while breast milk jaundice is caused by substances in the breast milk that can increase bilirubin levels.

**Correct Answer: D. Breastfeeding jaundice can be treated with phototherapy.**