Aedes aegypti is a vector for

Options

A. Yellow fever
B. Dengue fever
C. Japanese encephalitis
D. Both A and B.

Answer

**Step-by-Step Solution:**

1. **Identify the Organism**: Aedes aegypti is a species of mosquito known for its role in transmitting various diseases.

2. **Understand the Role of Aedes aegypti**: This mosquito acts as a vector, which means it carries pathogens from one host to another, facilitating the spread of diseases.

3. **List the Diseases Transmitted**: Aedes aegypti is known to transmit several viruses, including:
- Dengue virus
- Yellow fever virus
- Chikungunya virus
- Zika virus

4. **Analyze the Options**: The question provides several options:
- Yellow fever
- Dengue fever
- Japanese encephalitis
- Both A and B (Yellow fever and Dengue fever)

5. **Evaluate Each Option**:
- **Yellow fever**: Correct, as Aedes aegypti transmits this virus.
- **Dengue fever**: Correct, as Aedes aegypti also transmits this virus.
- **Japanese encephalitis**: Incorrect, as this disease is primarily transmitted by other mosquito species, such as Culex mosquitoes.

6. **Determine the Correct Answer**: Since Aedes aegypti is a vector for both yellow fever and dengue fever, the correct answer is option 4: both A and B.

**Final Answer**: Aedes aegypti is a vector for both yellow fever and dengue fever.

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