Who proposed five-kingdom system of classification of organisms?

Explanation

**Step-by-Step Solution:**

1. **Understanding Classification**: The first step is to understand what classification means in biology. Classification is the process of grouping organisms based on shared characteristics.

2. **Identifying the Scientist**: The question specifically asks for the individual who proposed the five-kingdom system of classification.

3. **Recognizing the Contribution**: The five-kingdom system is a significant contribution to biological classification. It categorizes living organisms into five distinct kingdoms.

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