What type of plants are classified as angiosperms?

Angiosperms are defined as vascular plants that produce seeds enclosed within an ovary, typically part of a flower. This characteristic distinguishes them from gymnosperms, which have seeds that are not enclosed but rather exposed on cones or other structures. The presence of flowers and the formation of fruits that carry the seeds are key features of angiosperms, making them the most diverse and widespread group of plants on Earth.

In contrast, the other options describe different types of plant groups. For example, the first option refers to gymnosperms, which have naked seeds, while the second option mentions non-flowering plants, which are not applicable to angiosperms, as they specifically involve flowering varieties. The last option lists ferns and mosses, which are non-vascular plants and do not produce seeds at all. Thus, the described characteristics of angiosperms in the correct choice align with their definition and role in plant biology.