In marginal placentation, the ovules are arranged-

Options

A. Along the inner wall of the carpel in a syncarpous ovary
B. Along the margin of single carpel
C. in the middle of the ovary
D. to the base of the ovary

Answer

**Step-by-Step Solution:**

1. **Understanding Placentation**: Placentation refers to the arrangement of ovules within the ovary of a flower. It is essential to know how these ovules are positioned, as it can vary among different plant species.

2. **Identifying Marginal Placentation**: In marginal placentation, the ovules are specifically arranged along the inner wall of the ovary. This arrangement occurs in a syncarpous ovary, which consists of multiple carpels fused together.

3. **Characteristics of Marginal Placentation**: The key feature of marginal placentation is that the ovules are located along the margin of the ovary. This means they are positioned at the edge or side of the ovary rather than in the center or base.

4. **Examples of Marginal Placentation**: Common examples of plants exhibiting marginal placentation include mustard (Brassica) and Dianthus. These plants have their ovules arranged in the characteristic manner of marginal placentation.

5. **Conclusion**: Based on the definition and characteristics of marginal placentation, the correct answer to the question is that in marginal placentation, the ovules are arranged along the margin of the single carpel.

**Final Answer**: The ovules are arranged along the margin of the single carpel.

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