An example of axile placentation is

Options

A. Lemon
B. Marigold
C. Argemone
D. Dianthus

Answer

### Step-by-Step Solution:

1. **Understanding Placentation**:
- Placentation refers to the arrangement of ovules within the ovary of a flower. It is crucial to understand this concept to identify different types of placentation.

2. **Defining Axile Placentation**:
- Axile placentation is characterized by the arrangement of ovules around a central axis within a compound ovary. This arrangement is formed by the fusion of septa, which divide the ovary into locules (chambers).

3. **Analyzing the Options**:
- The question provides four options: Lemon, Marigold, Argemone, and Dianthus. We need to evaluate each option to determine which one exhibits axile placentation.

4. **Evaluating Each Option**:
- **Lemon**: The structure of the lemon fruit shows axile placentation, where ovules are arranged around the central axis of the ovary.
- **Marigold**: In marigold, the placentation is basal, which means the ovules are attached at the base of the ovary.
- **Argemone**: Argemone exhibits parietal placentation, where ovules are attached to the walls of the ovary.
- **Dianthus**: In dianthus, the placentation is free central, which means the ovules are attached to a central column but not in a true axile arrangement.

5. **Conclusion**:
- After analyzing all options, the correct answer is **Lemon**, as it is the only example that demonstrates axile placentation.

### Final Answer:
An example of axile placentation is **Lemon**.