**Core Concept**
The treatment of pulmonary tuberculosis (TB) involves a combination of antibiotics to effectively kill the Mycobacterium tuberculosis bacteria. The World Health Organization (WHO) recommends a standardized regimen for treating new sputum-positive cases of pulmonary TB. This regimen typically includes a combination of first-line anti-TB drugs, which have been shown to be effective in curing the disease.

**Why the Correct Answer is Right**
The correct answer, C. RMP + INH + PZM + ETM, represents the standard first-line treatment regimen for recently sputum-positive cases of pulmonary TB. RMP (Rifampicin), INH (Isoniazid), PZM (Pyrazinamide), and ETM (Ethambutol) are all first-line anti-TB medications. Rifampicin and Isoniazid are bactericidal agents that work by inhibiting the synthesis of essential bacterial components, while Pyrazinamide has a unique mechanism of action that targets the dormant bacilli in the acidic environment of the macrophages. Ethambutol, on the other hand, inhibits the synthesis of the bacterial cell wall. The combination of these four drugs is essential for effectively treating pulmonary TB, as it addresses the various stages of the disease and prevents the development of drug resistance.

**Why Each Wrong Option is Incorrect**
**Option A:** This combination is missing Ethambutol, which is a crucial component of the standard first-line treatment regimen for pulmonary TB.

**Option B:** This combination includes Streptomycin (SMC), which is a second-line anti-TB medication that is not recommended for the initial treatment of new sputum-positive cases of pulmonary TB.

**Option D:** This combination is missing Pyrazinamide, which is essential for treating the dormant bacilli in the acidic environment of the macrophages.

**Clinical Pearl / High-Yield Fact**
It's essential to note that the treatment regimen for pulmonary TB may vary depending on factors such as the patient's resistance pattern, the presence of extrapulmonary TB, and the patient's adherence to treatment. Therefore, it's crucial to follow the guidelines recommended by the WHO and local health authorities to ensure effective treatment and prevent the development of drug resistance.

**✓ Correct Answer: C. RMP + INH + PZM + ETM**