**Core Concept:** Bacille Calmette-Guérin (BCG) is an attenuated strain of Mycobacterium bovis, primarily used as a vaccine against tuberculosis (TB). It also exhibits some protection against disseminated forms of the disease in infants and immunocompromised patients.

**Why the Correct Answer is Right:** BCG vaccination is a form of active immunotherapy that stimulates the immune system to produce a specific response against Mycobacterium tuberculosis, the causative agent of TB. This leads to a heightened immune response, potentially reducing the risk of TB infection or progression to active disease.

**Why Each Wrong Option is Incorrect:**

A. False: BCG vaccination primarily targets TB and has limited effectiveness against pulmonary TB in adults.
B. False: BCG vaccination does not provide complete protection against TB and is not a substitute for proper hygiene, sanitation, and infection control measures.
C. False: Although BCG vaccination may reduce the severity of TB disease, it does not eliminate the risk of developing TB altogether.
D. False: BCG vaccination does not provide protection against non-tuberculous mycobacterial infections, such as those caused by Mycobacterium avium complex (MAC).

**Clinical Pearl:** The primary use of BCG vaccination is in preventing severe forms of TB in infants and immunocompromised individuals, and as a diagnostic tool in distinguishing between latent TB infection and active TB disease.

**Correct Answer:** C. False: Although BCG vaccination may reduce the severity of TB disease, it does not eliminate the risk of developing TB altogether.