A sexually transmitted disease caused by bacteria is

Options

A. Leprosy
B. AIDS
C. Syphilis
D. Pertussis

Answer

To answer the question "A sexually transmitted disease caused by bacteria is," we will analyze the options provided and identify the correct answer step by step.

### Step-by-Step Solution:

1. **Understand the Question**: The question is asking for a sexually transmitted disease (STD) that is specifically caused by bacteria.

2. **Evaluate the Options**:
- **Option A: Leprosy**: Leprosy is caused by the bacterium Mycobacterium leprae. However, it is not classified as a sexually transmitted disease; it primarily affects the skin, nerves, and mucous membranes. Thus, this option is incorrect.

- **Option B: AIDS**: AIDS (Acquired Immunodeficiency Syndrome) is caused by the Human Immunodeficiency Virus (HIV), which is a virus, not a bacterium. Therefore, this option is also incorrect.

- **Option C: Syphilis**: Syphilis is indeed a sexually transmitted disease caused by the bacterium Treponema pallidum. This option fits the criteria of the question.

- **Option D: Pertussis**: Pertussis, also known as whooping cough, is caused by the bacterium Bordetella pertussis. However, it is not a sexually transmitted disease; it is a respiratory illness. Thus, this option is incorrect.

3. **Conclusion**: After evaluating all the options, the only sexually transmitted disease caused by bacteria is **Syphilis**.

### Final Answer:
The sexually transmitted disease caused by bacteria is **Syphilis**.

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