The bionomial system of nomenclature was initially proposed by :-

Options

A. Magnus
B. Bauhin
C. Caesalpinno
D. Discorides

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the origin of the binomial system of nomenclature, specifically who initially proposed it.

2. **Reviewing the Options**: The options provided are Magnus, Bohin, Sezel-Pinot, and Discorides. We need to evaluate each option to determine which one is correct.

3. **Evaluating Option 1 - Magnus**: Magnus is known for distinguishing between monocots and dicots, but he did not propose the binomial system of nomenclature. Therefore, this option is incorrect.

4. **Evaluating Option 2 - Bohin**: Caspar Bohen is credited with introducing the binomial system of nomenclature in 1623. He proposed that each species should have two names: a generic name and a specific epithet. This makes this option the correct answer.

5. **Evaluating Option 3 - Sezel-Pinot**: Cazalbino, also known as Sezel-Pinot, focused more on the classification of plants based on their reproductive organs rather than on the naming system. Thus, this option is incorrect.

6. **Evaluating Option 4 - Discorides**: Discorides was a botanist who contributed to herbal medicine but did not propose the binomial system of nomenclature. Therefore, this option is also incorrect.

7. **Conclusion**: After evaluating all options, the correct answer to the question is Caspar Bohen, as he was the one who initially proposed the binomial system of nomenclature.

**Final Answer**: The binomial system of nomenclature was initially proposed by Caspar Bohen.

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