Which of these is a STD ?

Options

A. Typhoid
B. Tetanus
C. Leprosy
D. Hepatitis-B

Answer

To determine which of the given diseases is a sexually transmitted disease (STD), we will analyze each option provided: typhoid, tetanus, leprosy, and hepatitis B.

### Step 1: Understand the definition of STD
- **Sexually Transmitted Diseases (STDs)** are infections that are primarily spread through sexual contact. They can be caused by bacteria, viruses, or parasites.

### Step 2: Analyze each option
1. **Typhoid**:
- Typhoid is caused by the bacterium *Salmonella typhi*.
- It is transmitted through contaminated food and water, not through sexual contact.
- **Conclusion**: Not an STD.

2. **Tetanus**:
- Tetanus is caused by the bacterium *Clostridium tetani*.
- It is typically contracted through wounds or cuts contaminated with the bacteria, not through sexual contact.
- **Conclusion**: Not an STD.

3. **Leprosy**:
- Leprosy is caused by the bacterium *Mycobacterium leprae*.
- It primarily spreads through prolonged close contact with an infected person, not through sexual contact.
- **Conclusion**: Not an STD.

4. **Hepatitis B**:
- Hepatitis B is caused by the Hepatitis B virus (HBV).
- It can be transmitted through sexual contact, as well as through blood and other body fluids.
- **Conclusion**: This is an STD.

### Final Answer
- The sexually transmitted disease (STD) among the options provided is **Hepatitis B**.

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