Which is caused by virus?

Options

A. Typhoid
B. tuberculosis
C. Polio
D. Diphtheria

Answer

To determine which disease is caused by a virus, we can analyze the options provided:

1. **Typhoid**: This disease is caused by bacteria, specifically *Salmonella Typhi*. Therefore, Typhoid is not caused by a virus.

2. **Tuberculosis (TB)**: This is also caused by bacteria, namely *Mycobacterium tuberculosis*. Thus, Tuberculosis is not a viral disease.

3. **Polio**: This disease is caused by a virus known as the poliovirus. Therefore, Polio is indeed caused by a virus.

4. **Diphtheria**: This infection is caused by bacteria, specifically *Corynebacterium diphtheriae*. Hence, Diphtheria is not caused by a virus.

Based on this analysis, the disease caused by a virus is **Polio**.

**Final Answer**: Polio is caused by a virus.

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