**Core Concept:** In cases where a mother has active Tuberculosis and is not on Anti-Tuberculosis Treatment (ATT), the newborn may be at risk for Tuberculosis infection or disease due to the mother's exposure. It is crucial to assess the newborn's risk and implement preventive measures accordingly.

**Why the Correct Answer is Right:**
A newborn exposed to Mycobacterium tuberculosis from an infected mother has a higher risk of developing Tuberculosis within the first year of life, particularly within the first six months. If the mother is not on ATT, the risk is considered higher. The World Health Organization (WHO) recommends Isoniazid preventive therapy (IPT) for infants born to mothers with active TB, even if the mother is on ATT. IPT reduces the risk of developing TB by about 60%.

**Why Each Wrong Option is Incorrect:**
A. Not mentioning IPT as a preventive measure and focusing on breastfeeding alone is incorrect because breastfeeding alone does not significantly reduce the risk of TB in infants.
B. Attributing the risk reduction solely to the mother's ATT is incorrect because IPT is the primary preventive measure for infants in this context.
C. Discussing exclusive breastfeeding and not mentioning IPT is also incorrect, as the question specifically mentions that the mother is not on ATT.
D. Discussing the risk of TB transmission through breastfeeding is partially correct, but the focus should be on the combination of IPT and avoiding close contact with the mother to reduce the risk further.

**Clinical Pearl:**
Infants born to mothers with active TB should receive IPT and avoid close contact with the mother for the first six months of life, when the risk of TB infection is highest. This approach reduces the risk of TB in infants by about 60%.

**Correct Answer:** D. Discussing the risk of TB transmission through breastfeeding and mentioning the importance of avoiding close contact with the mother to reduce the risk further.

Note: The correct answer is "D" because it addresses the primary preventive measures for infants born to mothers with active TB who are not on ATT, which is the focus of the question.