Which of the following disease has been eradicated from the world?

Options

A. Plague
B. Small pox
C. Poliomyelitis
D. Kala-azar

Answer

**Step-by-Step Solution:**

1. **Identify the Diseases Listed:**
The question presents four diseases: Plague, Smallpox, Poliomyelitis, and Kala Azar.

2. **Research Each Disease:**
- **Plague:** Caused by the bacterium Yersinia pestis, it is not eradicated and still occurs in some parts of the world.
- **Smallpox:** Caused by the variola virus, it was declared eradicated in 1979 by the World Health Organization (WHO).
- **Poliomyelitis:** Caused by the poliovirus, it has seen significant reduction due to vaccination but is not completely eradicated.
- **Kala Azar:** Also known as visceral leishmaniasis, it is caused by the Leishmania parasite and is not eradicated.

3. **Determine the Correct Answer:**
Based on the research, Smallpox is the only disease among the options that has been completely eradicated from the world.

4. **Final Answer:**
Therefore, the disease that has been eradicated from the world is **Smallpox**.

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