In parietal placentation, the ovary is usually one chambered but appears two chambered because of the formation of false septum called replum. Generally argemone and mustard show this type of placentation. so, option d is correct.

Structure of the Ovary

The ovary is a female reproductive organ that produces eggs (ova) and hormones such as estrogen and progesterone. It is an essential component of the female reproductive system.

Types of Ovarian Placentation

Ovarian placentation refers to the arrangement of placental tissue within the ovary. There are four types of ovarian placentation:

1) Axile Placentation: In axile placentation, the ovary is divided into several chambers or locules by the formation of partitions called septa. Each locule contains one or more ovules. Examples of plants with axile placentation include tomato and potato.

2) Marginal Placentation: In marginal placentation, the placenta is located along the margin or edge of the ovary. The ovules are attached to the placenta by a stalk called the funicle. Examples of plants with marginal placentation include pea and beans.

3) Free Central Placentation: In free central placentation, the ovary is one-chambered, and the ovules are attached to a central column called the placenta. Examples of plants with free central placentation include primrose and evening primrose.

4) Parietal Placentation: In parietal placentation, the ovary is one-chambered, but it becomes two-chambered due to the formation of a false septum or placenta. The ovules are attached to the inner wall of the ovary. Examples of plants with parietal placentation include mustard and rose.

Conclusion

In parietal placentation, the ovary is initially one-chambered, but it becomes two-chambered due to the formation of a false septum or placenta. This type of placentation is observed in plants such as mustard and rose. Understanding the different types of ovarian placentation is important in plant taxonomy and reproductive biology.