Small blood vessel may get blocked in infection of

Options

A. Plasmodium ovale
B. P. vivax
C. P. malariae
D. P. falciparum.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks which infection leads to the blockage of small blood vessels. The options provided are different species of the Plasmodium protozoan.

2. **Identifying the Organism**: Plasmodium is a genus of protozoa that causes malaria. There are several species of Plasmodium, including Plasmodium ovale, Plasmodium vivax, Plasmodium malariae, and Plasmodium falciparum.

3. **Mechanism of Infection**: When a mosquito bites a human, it injects the Plasmodium parasites into the bloodstream. These parasites then invade red blood cells (RBCs) and replicate within them.

4. **Effect of Plasmodium falciparum**: Among the species listed, Plasmodium falciparum is known to cause the most severe form of malaria. It is particularly notorious for causing complications such as cerebral malaria.

5. **Sticky Nature of Infected RBCs**: In the case of Plasmodium falciparum infection, the infected RBCs produce sticky proteins on their surface. This stickiness causes the RBCs to adhere to the walls of small blood vessels.

6. **Resulting Blockage**: The adherence of these sticky RBCs to the blood vessel walls can lead to blockages. This blockage can restrict blood flow, leading to various complications, including organ damage.

7. **Conclusion**: Based on the information, the correct answer to the question is Plasmodium falciparum, as it is the species that causes blockage of small blood vessels during infection.

**Final Answer**: Plasmodium falciparum (Option 4).

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