A person suffering from malaria feels fever when

Options

A. RBC generally ruptured and haemozoin granules are released
B. Exo-erythrocytic cycle is completed
C. Singnet ring stage is formed
D. all of these

Answer

### Step-by-Step Solution:

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

2. **Infection Process**: When an infected mosquito bites a person, it injects sporozoites (the infective stage of the Plasmodium) into the bloodstream. These sporozoites travel to the liver.

3. **Liver Stage**: In the liver, the sporozoites undergo a process called the exoerythrocytic cycle, where they multiply and develop into merozoites.

4. **RBC Invasion**: After the liver stage, the merozoites are released into the bloodstream, where they invade red blood cells (RBCs).

5. **RBC Rupture**: The merozoites multiply within the RBCs and eventually cause the cells to rupture. This rupture releases toxic substances, including hemozoin granules, into the bloodstream.

6. **Fever Response**: The release of hemozoin and other toxic substances triggers the body’s immune response, leading to recurring fever. This fever typically occurs every 3 to 4 days, coinciding with the cycle of RBC rupture.

7. **Conclusion**: Therefore, a person suffering from malaria feels fever primarily when the RBCs are ruptured and hemozoin granules are released.

### Final Answer:
A person suffering from malaria feels fever when RBCs are generally ruptured and hemozoin granules are released.