Linnaeus proposed an outline of plant classification in

Options

A. Genera Plantarum
B. Species Plantarum
C. Systema Naturae
D. Philosophia Botanica

Answer

### Step-by-Step Solution:

1. **Identify the Question**: The question asks when Linnaeus proposed an outline of plant classification, providing four options to choose from.

2. **Understand Linnaeus's Contribution**: Linnaeus is known as the "father of taxonomy" due to his significant contributions to the classification and naming of organisms.

3. **Examine the Options**: The four options provided are:
- A) Genera Plantarum
- B) Species Plantarum
- C) Systema Naturae
- D) Philosophia Botanica

4. **Recall Linnaeus's Works**: Linnaeus wrote several important works in the field of botany and taxonomy. Among these, "Systema Naturae" is particularly notable for outlining his classification system for plants.

5. **Identify the Correct Answer**: Linnaeus proposed an outline of plant classification in "Systema Naturae," which is option C.

6. **Conclusion**: Therefore, the correct answer to the question is C) Systema Naturae.

### Final Answer:
Linnaeus proposed an outline of plant classification in **Systema Naturae**.

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