A person with sickle cell anaemia is

Options

A. (a) More prone to malaria
B. (b) More prone to typhoid
C. (c) Less prone to malaria
D. (d) Less prone to typhoid

Answer

### Step-by-Step Solution:

1. **Understanding Sickle Cell Anemia**:
- Sickle cell anemia is an autosomal recessive genetic disorder characterized by the distortion of red blood cells (RBCs) into a sickle shape. This abnormal shape affects the functionality of the RBCs.

2. **Effects on the Body**:
- The sickle-shaped RBCs impair splenic function, which is crucial for the production and regulation of healthy RBCs. This impairment leads to a shortage of healthy RBCs and restricted blood flow.

3. **Analyzing the Options**:
- **Option A**: "A person with sickle cell anemia is more prone to malaria."
- This statement is incorrect. Individuals with sickle cell anemia are actually less prone to malaria.
- **Option B**: "A person with sickle cell anemia is more prone to typhoid."
- This statement is also incorrect. Typhoid fever is caused by bacteria that infect white blood cells (WBCs) and does not directly affect RBCs.
- **Option C**: "A person with sickle cell anemia is less prone to malaria."
- This statement is correct. The sickle-shaped RBCs are less susceptible to infection by the malaria parasite (Plasmodium species) because the parasite cannot effectively penetrate and rupture these distorted cells.

4. **Conclusion**:
- Based on the analysis, the correct answer is **Option C**: A person with sickle cell anemia is less prone to malaria.