…………….... classified animals into two groups, those which have red blood and those that did not.

Options

A. Aristotle
B. Theophrastus
C. Linnaeus
D. Whittaker

Answer

To answer the question, we need to identify the scientist who classified animals into two groups based on the presence or absence of red blood cells.

### Step-by-Step Solution:

1. **Understanding the Classification**: The question states that animals were classified into two groups: those with red blood and those without. This indicates a very early form of biological classification based on a physiological characteristic.

2. **Identifying the Scientist**: The video transcript mentions several scientists, including Aristotle, Theophrastus, Linnaeus, and Vivitacus. However, it specifically highlights Aristotle as the one who made this classification.

3. **Defining the Groups**: According to the transcript, Aristotle divided animals into two main groups:
- **Anemia**: This group included animals that do not have red blood cells (RBCs), which are primarily invertebrates.
- **Enema**: This group included animals that have red blood cells, which are primarily vertebrates.

4. **Conclusion**: Based on the information provided, the correct answer to the question is Aristotle, as he was the scientist who first classified animals into these two groups based on the presence or absence of red blood cells.

### Final Answer:
Aristotle