Yellow fever is transmitted by

Options

A. Culex
B. Aedes
C. Anopheles
D. Bed Bug.

Answer

### Step-by-Step Solution:

1. **Understanding Yellow Fever**: Yellow fever is a viral disease caused by the flavivirus. It is known for causing hemorrhagic fever, which can lead to high fever and bleeding into the skin.

2. **Identifying the Vector**: The question asks about the transmission of yellow fever. The primary vector responsible for transmitting yellow fever is a mosquito.

3. **Recognizing the Specific Mosquito**: Among the various types of mosquitoes, the Aedes mosquito is specifically known for transmitting yellow fever. This mosquito acquires the virus by feeding on infected primates, which can include both humans and non-human primates.

4. **Eliminating Other Options**:
- **Culex Mosquito**: This type of mosquito is known for transmitting diseases like West Nile Virus and encephalitis, not yellow fever.
- **Anopheles Mosquito**: This mosquito is primarily responsible for spreading malaria.
- **Bed Bug**: Bed bugs do not transmit any viral diseases; they may cause skin infections but are not vectors for yellow fever.

5. **Conclusion**: Based on the information, the correct answer to the question "Yellow fever is transmitted by" is the Aedes mosquito.

### Final Answer:
Yellow fever is transmitted by the Aedes mosquito.

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