Who among the following is not a naturalist?

Options

A. Darwin
B. Malthus
C. Wallace
D. All of the above

Answer

To determine who among the following is not a naturalist, we need to analyze the individuals mentioned in the question: Darwin, Malthus, and Wallace.

### Step-by-Step Solution:

1. **Identify the Individuals**:
- The question lists three individuals: Darwin, Malthus, and Wallace.

2. **Research on Darwin**:
- Charles Darwin is well-known for his contributions to the theory of evolution through natural selection. He is widely recognized as a naturalist.

3. **Research on Wallace**:
- Alfred Russel Wallace is also recognized as a naturalist. He independently conceived the theory of evolution through natural selection and collaborated with Darwin in publishing their ideas.

4. **Research on Malthus**:
- Thomas Robert Malthus was an economist and demographer. He is best known for his theories on population growth and its implications, particularly in his work "An Essay on the Principle of Population." He is not classified as a naturalist.

5. **Conclusion**:
- Since both Darwin and Wallace are naturalists, while Malthus is not, the answer to the question is Malthus.

### Final Answer:
The individual who is not a naturalist is **Malthus**.

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