Aedes and Anopheles are

Options

A. bacteria
B. protozoans
C. algae
D. none of these.

Explanation

**Step-by-Step Solution:**

1. **Identify the Organisms:**
- The question mentions two organisms: Aedes and Anopheles.

2. **Determine the Classification:**
- Aedes and Anopheles are not bacteria, protozoa, or algae. They are types of mosquitoes.

3. **Understand Their Role:**
- Both Aedes and Anopheles mosquitoes serve as vectors for disease transmission. This means they carry and spread pathogens that cause diseases.

4. **Identify the Diseases They Transmit:**
- Aedes mosquitoes are known for transmitting dengue fever, which is caused by the dengue virus.
- Anopheles mosquitoes are known for transmitting malaria, which is caused by the Plasmodium protozoan.

5. **Conclusion:**
- Since Aedes and Anopheles are mosquitoes (insects) and not classified under bacteria, protozoa, or algae, the correct answer to the question is "none of these."

**Final Answer:**
Aedes and Anopheles are none of these (they are mosquitoes).

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