A person with sickle cell anaemia is

Options

A. more prone to malaria
B. more prone to typhoid
C. less prone to malaria
D. less prone to typhoid.

Explanation

**Step-by-Step Solution:**

1. **Understanding Sickle Cell Anemia**: Sickle cell anemia is a genetic blood disorder characterized by the production of abnormal hemoglobin, known as hemoglobin S. This causes red blood cells to become rigid and shaped like a sickle or crescent.

2. **Sickle Cell Trait and Malaria**: Individuals with sickle cell trait (carriers of one sickle cell gene) or sickle cell anemia (those with two sickle cell genes) have some level of protection against malaria. This is because the malaria parasite, Plasmodium, has difficulty infecting sickle-shaped red blood cells.

3. **Mechanism of Protection**: The sickle-shaped red blood cells create an environment that is less hospitable for the malaria parasite. The abnormal hemoglobin interferes with the parasite's ability to penetrate and multiply within the red blood cells.

4. **Conclusion**: Therefore, a person with sickle cell anemia is less prone to malaria due to the protective effect of the sickle-shaped red blood cells against the malaria parasite.

**Final Answer**: A person with sickle cell anemia is less prone to malaria.

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