The malarial parasite was discovered in the RBCs of human beings by

Options

A. Haldane
B. Laveran
C. Ronald Ross
D. Stephans

Answer

To answer the question, "The malarial parasite was discovered in the RBCs of human beings by?", we will follow these steps:

### Step-by-Step Solution:

1. **Understand the Question**: The question asks for the name of the person who discovered the malarial parasite, specifically Plasmodium, in the red blood cells (RBCs) of humans.

2. **Identify the Malarial Parasite**: The causative agent of malaria is the genus Plasmodium, which has several species including Plasmodium vivax, Plasmodium ovale, Plasmodium malariae, and Plasmodium falciparum.

3. **Know the Discovery Context**: The discovery of the malarial parasite in human RBCs is a significant historical event in medicine. It is important to note that the discovery was made in the context of understanding malaria and its transmission.

4. **Review the Options**: The options provided are:
- A) Haldane
- B) Leveran
- C) Ronald Ross
- D) Stephens

5. **Recall Historical Figures**:
- Ronald Ross is known for discovering the life cycle of the malaria parasite in mosquitoes.
- Charles Louis Alfonso Laveran (often referred to as Leveran) was a French physician who identified the malaria parasite in the blood of patients.

6. **Select the Correct Answer**: Based on historical records, Charles Louis Alfonso Laveran is credited with the discovery of the malarial parasite in human RBCs. He won the Nobel Prize in Physiology and Medicine in 1907 for this discovery.

7. **Final Answer**: The correct answer is **B) Leveran**.