## **Core Concept**
The question tests knowledge of anti-tuberculosis (TB) drugs and their safety profiles during pregnancy. Certain anti-TB drugs are known to have teratogenic effects or pose risks to the fetus, necessitating careful selection during pregnancy.

## **Why the Correct Answer is Right**
The correct answer, , refers to the drug Streptomycin. Streptomycin is an aminoglycoside antibiotic used in the treatment of TB. It is known to cause ototoxicity in the fetus, leading to congenital deafness. Due to this significant risk, Streptomycin is contraindicated throughout pregnancy.

## **Why Each Wrong Option is Incorrect**
- **Option A:** - This option is incorrect because is not specified, but commonly used anti-TB drugs like Isoniazid, Rifampicin, and Ethambutol have different safety profiles during pregnancy and are not entirely contraindicated.
- **Option B:** - Without a specific drug mentioned, it's hard to address directly, but many first-line anti-TB drugs have guidelines for use during pregnancy.
- **Option C:** - Similarly, without specifics, it's challenging, but drugs like Pyrazinamide are used with caution.
- **Option D:** - This option is incorrect as it does not provide a drug name.

## **Clinical Pearl / High-Yield Fact**
A critical point to remember is that Streptomycin, an aminoglycoside used in TB treatment, is strictly avoided in pregnancy due to its potential to cause fetal ototoxicity. Pregnant women with TB require careful management, often involving first-line drugs like Isoniazid, Rifampicin, and Ethambutol, with close monitoring.

## **Correct Answer:** . Streptomycin