Tuberculosis is caused by

Options

A. Mycobacterium
B. Vibrio
C. Clostridium
D. None of these

Answer

To answer the question "Tuberculosis is caused by," we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Options**: The question provides four options:
- Mycobacterium
- Vibrio
- Clostridium
- None of these

2. **Analyze Each Option**:
- **Clostridium**: This is a group of bacteria that includes species such as Clostridium tetani, which causes tetanus. Tetanus is characterized by muscle stiffness and spasms, particularly in the jaw, hence the term "lockjaw." Therefore, Clostridium does not cause tuberculosis.
- **Vibrio**: This group includes Vibrio cholerae, which is responsible for cholera, a waterborne disease. Since cholera is not related to tuberculosis, Vibrio is not the correct answer.
- **Mycobacterium**: This is the key option. Mycobacterium tuberculosis is the specific bacterium that causes tuberculosis. It is a slow-growing bacterium that primarily affects the lungs but can also impact other parts of the body.
- **None of these**: Given that Mycobacterium is the correct answer, this option is also incorrect.

3. **Conclusion**: After analyzing all the options, it is clear that tuberculosis is caused by Mycobacterium, specifically Mycobacterium tuberculosis.

### Final Answer:
**Tuberculosis is caused by Mycobacterium.**

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