Parietal placentation is observed in

Options

A. Dianthus
B. Pisum
C. Primrose
D. Argemone

Answer

To solve the question regarding which plant exhibits parietal placentation, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Parietal Placentation**:
- Parietal placentation is a type of placentation where ovules develop on the inner wall of a one-chambered ovary or on the periphery.
- It can occur in unilocular ovaries, and the placenta forms a false septum that divides the ovary into two chambers.

2. **Analyzing the Options**:
- **Dianthus**: Known for free central placentation.
- **Pisum (Pea)**: Exhibits marginal placentation.
- **Primrose**: Also shows free central placentation.
- **Argimon (Mustard)**: Known to exhibit parietal placentation.

3. **Identifying the Correct Answer**:
- Based on the characteristics of each plant, Argimon (Mustard) is the only option that shows parietal placentation.

### Conclusion:
The correct answer is **Argimon**.