**Core Concept**
In a patient with active tuberculosis (TB), particularly during pregnancy, the management involves balancing the need to treat the mother's TB with the potential risks to the fetus. The primary goal is to prevent maternal mortality and morbidity while minimizing the risks to the baby.

**Why the Correct Answer is Right**
The treatment of active TB in pregnancy typically involves a combination of first-line antitubercular medications, including isoniazid (INH), rifampicin (RIF), pyrazinamide (PZA), and ethambutol (EMB). However, streptomycin (SM), an aminoglycoside antibiotic, is contraindicated in pregnancy due to its potential to cause congenital deafness and ototoxicity in the fetus.

**Why Each Wrong Option is Incorrect**
**Option A:** Isoniazid (INH) is a critical component of TB treatment in pregnancy and is generally considered safe.
**Option B:** Rifampicin (RIF) is also a first-line antitubercular medication that is commonly used in pregnancy.
**Option C:** Pyrazinamide (PZA) is another essential medication in the treatment of TB and is not contraindicated in pregnancy.

**Clinical Pearl / High-Yield Fact**
The World Health Organization (WHO) recommends that TB treatment in pregnancy should be continued throughout the entire gestation period, including during labor and postpartum, to prevent relapse and minimize the risk of TB transmission to the baby.

**Correct Answer:** D. Streptomycin (SM) is contraindicated in pregnancy due to its potential to cause congenital deafness and ototoxicity in the fetus.