Carrier of malaria-causing protozoan is ________.

Options

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

Answer

**Step-by-Step Solution:**

1. **Identify the Disease**: The question asks about the carrier of a disease caused by a protozoan. In this case, we are looking for the carrier of malaria.

2. **Understand the Causative Agent**: The protozoan that causes malaria is known as Plasmodium. It is important to know what organism is responsible for the disease to identify its carrier.

3. **Identify the Carrier**: The carrier of the malaria-causing protozoan (Plasmodium) is a specific type of mosquito.

4. **Select the Correct Option**: Among the options provided (female Anopheles mosquito, cockroach, housefly, butterfly), the correct answer is the female Anopheles mosquito. This mosquito is known to transmit the Plasmodium protozoan when it bites an infected person.

5. **Explain the Transmission**: When a female Anopheles mosquito bites an infected person, it ingests the Plasmodium. The protozoan then travels to the mosquito's salivary glands. When this mosquito bites a healthy person, it injects the Plasmodium into their bloodstream, leading to malaria.

6. **Conclusion**: Therefore, the carrier of the malaria-causing protozoan is the female Anopheles mosquito.

**Final Answer**: The carrier of malaria-causing protozoan is **female Anopheles mosquito**.

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