Blood circulation was discovered by

Options

A. William Harvey
B. Hippocrates
C. Karl Landsteiner
D. Paul Ehrlich

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks who discovered blood circulation.

2. **Recall Historical Figures**: Consider the prominent scientists in the field of medicine and physiology. Notable figures include William Harvey, Hippocrates, Karl Landsteiner, and Paul Ehrlich.

3. **Analyze Each Option**:
- **William Harvey**: He is known for his work on the circulation of blood. He proposed that blood circulates continuously through the body in a closed system.
- **Hippocrates**: Known as the "Father of Medicine," he contributed to early medical practices but did not discover blood circulation.
- **Karl Landsteiner**: He is famous for discovering blood groups and classifying them, but he did not discover blood circulation.
- **Paul Ehrlich**: Recognized for his work in chemotherapy, he did not contribute to the understanding of blood circulation.

4. **Conclude the Correct Answer**: Based on the analysis, the correct answer is William Harvey, as he was the one who discovered and described the circulation of blood.

5. **Final Answer**: Blood circulation was discovered by William Harvey.

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