**Core Concept**
Tuberculosis, a chronic bacterial infection caused by Mycobacterium tuberculosis, is often referred to as the "White Plague" due to its historical impact on European populations during the Middle Ages.

**Why the Correct Answer is Right**
The term "White Plague" is attributed to tuberculosis due to its high mortality rate and the pale, emaciated appearance of patients suffering from the disease. Tuberculosis affects primarily the lungs but can also affect other parts of the body, such as the kidneys, spine, and brain. The disease is transmitted through the air when an infected person coughs, sneezes, or talks, releasing droplets containing the bacteria.

**Why Each Wrong Option is Incorrect**
**Option A:** Pneumonic Plague refers to the pulmonary form of plague caused by Yersinia pestis, which is characterized by a sudden onset of symptoms, including fever, chills, and cough, but it is not commonly referred to as the "White Plague."

**Option B:** Bubonic Plague is the most common form of plague, characterized by the formation of swollen lymph nodes, or "buboes," in the groin, armpits, or neck. This form of plague is also caused by Yersinia pestis and is not typically referred to as the "White Plague."

**Option D:** Leprosy, caused by Mycobacterium leprae, is a chronic bacterial infection affecting the skin, nerves, and mucous membranes. While it is a significant public health concern, leprosy is not commonly referred to as the "White Plague."

**Clinical Pearl / High-Yield Fact**
Tuberculosis is a leading cause of death worldwide, with an estimated 1.5 million deaths in 2020. The disease is often associated with malnutrition, HIV/AIDS, and other underlying health conditions, making it a significant public health concern in low- and middle-income countries.

**✓ Correct Answer: C. Tuberculosis**