In_________placentation, a monocarpellary overy bears a sigle longitudinal ovule along the junction of two fused margins.

Options

A. axile
B. parietal
C. free central
D. marginal

Explanation

**Step-by-Step Text Solution:**

1. **Understanding the Question**: The question asks about a specific type of placentation in flowering plants where a monocarpellary ovary contains a single longitudinal ovule along the junction of two fused margins.

2. **Identifying Types of Placentation**: There are several types of placentation in flowering plants, including:
- Axile
- Parietal
- Free central
- Marginal

3. **Defining Marginal Placentation**: In marginal placentation, the ovules are attached along the margin of the ovary. This occurs in a monocarpellary (single carpel) and unilocular (single chamber) ovary. The ovules develop along the fused margins of the carpel.

4. **Examples of Marginal Placentation**: This type of placentation is commonly found in plants belonging to the legume family (Leguminosae).

5. **Conclusion**: Based on the characteristics of marginal placentation, the correct answer to the question is "marginal".

**Final Answer**: In **marginal** placentation, a monocarpellary ovary bears a single longitudinal ovule along the junction of two fused margins.

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