Malaria is caused by

Options

A. Plasmodium vivax
B. Plasmodium malariae
C. Plasmodium falcipaum
D. All of these

Answer

**Step-by-Step Solution:**

1. **Understanding Malaria**: Malaria is a disease that is transmitted through the bite of infected female Anopheles mosquitoes. It is important to recognize that malaria is a vector-borne disease.

2. **Identifying the Causative Agent**: The disease is caused by a group of single-celled organisms known as protozoa. The specific protozoan responsible for malaria is from the genus Plasmodium.

3. **Types of Plasmodium**: There are several species of Plasmodium that can cause malaria in humans:
- **Plasmodium vivax**: This species is prevalent in regions like Asia and South America and is known to cause malaria.
- **Plasmodium malariae**: This species is less common and is primarily found in Africa, but it can also cause malaria.
- **Plasmodium falciparum**: This is the most dangerous and common species responsible for the majority of malaria-related deaths worldwide.

4. **Conclusion**: Since all three species mentioned (Plasmodium vivax, Plasmodium malariae, and Plasmodium falciparum) can cause malaria, the correct answer to the question "Malaria is caused by" is option D: all of these.

**Final Answer**: Malaria is caused by Plasmodium vivax, Plasmodium malariae, and Plasmodium falciparum.

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