## Core Concept
The management of a newborn whose mother has active tuberculosis (TB) and is taking anti-tubercular therapy (ATT) involves preventing the transmission of TB to the newborn while also considering the newborn's potential exposure to first-line ATT drugs. The approach must balance the risk of TB transmission with the potential effects of ATT on the newborn.

## Why the Correct Answer is Right
The correct approach involves **separating the newborn from the mother** until the mother is no longer infectious, **administering isoniazid prophylaxis** to the newborn, and **monitoring for signs of TB**. This approach helps prevent the transmission of TB to the newborn. Isoniazid prophylaxis is recommended for newborns exposed to active TB, especially if the mother is not considered fully infectious or if the newborn's exposure is limited.

## Why Each Wrong Option is Incorrect
- **Option A:** This option is incorrect because simply isolating the newborn without providing any preventive therapy does not adequately address the risk of TB transmission.
- **Option B:** This option is incorrect because giving the newborn ATT without proper evaluation may lead to unnecessary side effects and does not consider the newborn's specific risk factors or potential for TB disease.
- **Option C:** This option might seem partially correct but is not the best approach as it lacks specifics on prophylaxis or monitoring.

## Clinical Pearl / High-Yield Fact
A key point to remember is that **newborns of mothers with active TB should receive isoniazid prophylaxis** (10 mg/kg/day for 6 months) after ruling out TB disease in the newborn. The newborn should also be monitored closely for signs of TB. Additionally, ensuring the mother is on effective ATT and not infectious before resuming close contact is crucial.

## Correct Answer: D.