Black water fever is caused by:

Options

A. (a) Plasmodium vivax
B. (b) Plasmodium malareie
C. (c) Plasmodium ovale
D. (d) Plasmodium falciparum

Answer

**Step-by-Step Solution:**

1. **Understanding Black Water Fever**: Black water fever is a clinical syndrome that arises as a complication of malaria. It is associated with severe symptoms and can be fatal.

2. **Causes of Black Water Fever**: The condition is believed to be caused by an autoimmune reaction between the malarial parasite and a drug called quinine. This reaction leads to severe health complications.

3. **Symptoms of Black Water Fever**: The primary symptoms include intravascular hemolysis, which is the rapid destruction of red blood cells (RBCs) in the bloodstream. This destruction can lead to hemoglobinuria, which is the presence of blood in urine. Additionally, the condition can lead to kidney failure.

4. **Identifying the Plasmodium Species**: There are several species of Plasmodium that cause malaria, but the one most commonly associated with black water fever is **Plasmodium falciparum**. This species is known for being the most virulent and has a unique ability to rapidly bind to red blood cells, which contributes to the severity of the disease.

5. **Conclusion**: Therefore, the correct answer to the question "Black water fever is caused by:" is **Plasmodium falciparum**.

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