The disease caused by viruses is

Options

A. Tuberculosis
B. Smallpox
C. Cholera
D. Typhoid

Answer

To determine which disease is caused by viruses among the given options, we can analyze each option step by step:

1. **Option 1: Tuberculosis**
- Tuberculosis is caused by the bacterium *Mycobacterium tuberculosis*.
- Since it is a bacterial disease, this option is not the correct answer.

2. **Option 2: Smallpox**
- Smallpox is caused by the variola virus, which is a member of the virus family.
- As this is a viral disease, this option could be the correct answer.

3. **Option 3: Cholera**
- Cholera is caused by the bacterium *Vibrio cholerae*.
- Since it is a bacterial disease, this option is not the correct answer.

4. **Option 4: Typhoid**
- Typhoid is caused by the bacterium *Salmonella typhi*.
- As it is also a bacterial disease, this option is not the correct answer.

After analyzing all the options, we conclude that the only disease caused by viruses among the given options is **smallpox**.

**Final Answer: Smallpox**

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