A viral disease is

Options

A. Cancer
B. Leukemia
C. Typhoid
D. Yellow fever

Answer

**Step-by-Step Solution:**

1. **Understand the Question**: The question asks to identify which of the given options is a viral disease.

2. **Analyze Each Option**:
- **Option A: Cancer**: Cancer is not a viral disease; it is characterized by uncontrolled cell division and can lead to tumor formation. Therefore, this option is incorrect.
- **Option B: Leukemia**: Leukemia is a type of cancer that affects blood cells and is also not a viral disease. This option is also incorrect.
- **Option C: Bacterial Infection (Salmonella)**: This option refers to a bacterial disease caused by Salmonella bacteria. Since it is a bacterial infection, it is not a viral disease. Thus, this option is incorrect.
- **Option D: Yellow Fever**: Yellow fever is a viral infection caused by the yellow fever virus, which belongs to the flavivirus genus. It is transmitted by mosquitoes, specifically from the Aedes family. This option is correct.

3. **Conclusion**: The only option that correctly identifies a viral disease is **Option D: Yellow Fever**.

**Final Answer**: Yellow Fever

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