Carrier of malaria-causing protozoan is

Options

A. female Anopheles mosquito
B. cockroach
C. housefly
D. butterfly

Explanation

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks for the carrier of the malaria-causing protozoan. This means we need to identify which organism is responsible for transmitting the malaria parasite.

2. **Identifying the Disease**: Malaria is a disease caused by a protozoan parasite known as Plasmodium. This parasite is transmitted to humans through the bite of infected mosquitoes.

3. **Identifying the Carrier**: Among the options provided:
- A) Female Anopheles mosquito
- B) Cockroach
- C) Housefly
- D) Butterfly

We need to determine which of these organisms is known to carry the malaria-causing protozoan.

4. **Analyzing Each Option**:
- **Cockroach**: Not a carrier of malaria.
- **Housefly**: Not a carrier of malaria.
- **Butterfly**: Not a carrier of malaria.
- **Female Anopheles mosquito**: This is the known carrier of the Plasmodium parasite that causes malaria.

5. **Conclusion**: The correct answer is option A, the female Anopheles mosquito, as it is the only organism listed that is responsible for carrying and transmitting the malaria-causing protozoan.

### Final Answer:
The carrier of the malaria-causing protozoan is **A) Female Anopheles mosquito**.

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