A person suffering from a disease caused by Plasmodium, experiences recurring chill and fever at the time when
(a) the sporozoites released from RBCs are being rapidly killed and broken down inside spleen
(b) the trophozoites reach maximum growth and give out certain toxins
(c) the parasite after its rapid multiplication inside RBCs ruptures them, releasing the stage to enter fresh RBCs
(d) the microgametocytes and megagametocyte are being destroyed by the WBCs

Options

A. the sporozoites released from RBCs are being rapidly killed and broken down inside spleen
B. the trophozoites reach maximum growth and give out certain toxins
C. the parasite after its rapid multiplication inside RBCs ruptures them, releasing the stage to enter fresh RBCs
D. the microgametocytes and megagametocyte are being destroyed by the WBCs

Answer

To solve the question regarding the recurring chills and fever experienced by a person suffering from a disease caused by Plasmodium, we need to analyze the options provided and understand the life cycle of the Plasmodium parasite, which causes malaria.

### Step-by-Step Solution:

1. **Understanding the Disease**:
- Malaria is caused by the Plasmodium species, which is transmitted to humans through the bite of infected female Anopheles mosquitoes.

2. **Life Cycle of Plasmodium**:
- After entering the human body, the Plasmodium sporozoites travel to the liver, where they mature into merozoites.
- The merozoites then enter red blood cells (RBCs) and multiply.

3. **Erythrocytic Cycle**:
- Inside the RBCs, the merozoites develop into trophozoites and then into schizonts (also known as scyzoites).
- The schizonts eventually rupture the RBCs, releasing new merozoites into the bloodstream, which can then infect more RBCs.

4. **Symptoms of Malaria**:
- The rupture of RBCs and the release of toxins, particularly hemozoin, into the bloodstream is what triggers the recurring chills and fever associated with malaria. This cycle typically repeats every 48 to 72 hours.

5. **Analyzing the Options**:
- **Option (a)**: Incorrect. Sporozoites are not released from RBCs; they are the initial form that enters the body.
- **Option (b)**: Incorrect. While trophozoites do grow and produce toxins, the chills and fever are primarily due to the rupture of RBCs.
- **Option (c)**: Correct. The recurring chills and fever occur when the parasite multiplies rapidly inside RBCs and ruptures them, releasing merozoites and toxins into the bloodstream.
- **Option (d)**: Incorrect. The destruction of microgametocytes and macrogametocytes by WBCs does not cause the recurring symptoms.

### Conclusion:
The correct answer is **(c)**: the parasite after its rapid multiplication inside RBCs ruptures them, releasing the stage to enter fresh RBCs.

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