Roman art of the post-Mauryan period was famous for its mural paintings. These paintings were created on walls and ceilings of various structures, such as temples and palaces. They depicted a variety of subjects including religious and mythological scenes, portraits of rulers and important figures, and scenes from everyday life.

- Introduction to Roman art of the post-Mauryan period:
During the post-Mauryan period, which occurred between the 2nd century BCE and the 2nd century CE, the influence of Roman art and culture started to spread in the Indian subcontinent. This period saw the emergence of a unique artistic style that combined Roman and local Indian elements.

- Mural paintings:
The most prominent feature of Roman art during this period was its mural paintings. These paintings were characterized by their vibrant colors, intricate details, and realistic depiction of subjects. The artists used a variety of materials such as pigments, plaster, and stucco to create these paintings.

- Subjects depicted:
The mural paintings of the post-Mauryan period depicted a wide range of subjects. Religious and mythological scenes were often depicted, showcasing the influence of Indian mythology and Roman religious beliefs. Portraits of rulers and important figures were also common, emphasizing their status and power. Additionally, scenes from everyday life, such as hunting, dancing, and feasting, were also depicted in these paintings.

- Unrealistic nature:
Contrary to the statement, Roman art of the post-Mauryan period was not unrealistic in nature. In fact, it was known for its realistic depiction of subjects. The artists paid great attention to details, such as facial expressions, clothing, and gestures, to create lifelike representations.

- Conclusion:
In conclusion, the correct statement about Roman art of the post-Mauryan period is that it was famous for its mural paintings. These paintings depicted a variety of subjects, including religious and mythological scenes, portraits of rulers, and scenes from everyday life. The art was characterized by its vibrant colors and realistic depiction of subjects, showcasing the influence of both Roman and Indian artistic traditions.