Bentham and Hooker proposed their system of classification in

Options

A. Genera Plantarum
B. Species Plantarum
C. Historia Plantarum
D. Historia Nature

Answer

To answer the question about when Bentham and Hooker proposed their system of classification, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Authors**: Recognize that the question refers to Bentham and Hooker, who are known for their contributions to plant classification.

2. **Understand the Context**: Bentham and Hooker proposed a classification system that is primarily concerned with plants. Their work was significant in the field of botany.

3. **Know the Classification System**: They introduced a system of classification that is known as the "natural classification" system. This system is based on the natural relationships among plants rather than just morphological characteristics.

4. **Identify the Book**: The classification system was published in a book titled "Genera Plantarum". This book is a comprehensive work that details the classification of seed plants.

5. **Select the Correct Option**: Given the options provided in the question, the correct answer is "Genera Plantarum", which is option A.

### Final Answer:
Bentham and Hooker proposed their system of classification in "Genera Plantarum".

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