The term 'Protista' was introduced by a German Biologist and Philosopher

Options

A. (a) John Ray
B. (b) Robert Grant
C. (c) Ernst Haeckel
D. (d) Leuckart

Answer

To answer the question regarding who introduced the term 'Protista', we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Concept of Protista**:
- Protista is a kingdom in biological classification that includes unicellular eukaryotic organisms. These organisms are characterized by having a well-defined nucleus and are primarily single-celled.

2. **Historical Context**:
- The study of protists began in the 19th century. The first observations of these organisms were made by John Hogg in 1860.

3. **Introduction of the Term**:
- The term 'Protista' was introduced later, in 1866, by a German biologist and philosopher named Ernst Haeckel. He used the term to classify these unicellular eukaryotes.

4. **Identify the Correct Option**:
- Given the options, we need to identify who among them is Ernst Haeckel, as he is the one who introduced the term 'Protista'.

5. **Conclusion**:
- Therefore, the correct answer to the question is Ernst Haeckel.

### Final Answer:
The term 'Protista' was introduced by Ernst Haeckel.

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