What structure is formed by the lower posterior of the ramus?

The correct choice refers to the Angle of the mandible, which is the point where the ramus of the mandible meets the body of the mandible. This structure is significant in dental and anatomical studies because it plays a crucial role in defining the contours of the jaw and is important for various dental procedures, as well as for understanding occlusion and jaw function.

The Angle of the mandible is clinically relevant as it can be a site for surgical interventions and has implications in orthodontics and prosthodontics. It serves as a landmark for practitioners when assessing facial symmetry and planning treatments.

In contrast, the ramus of the mandible itself simply refers to the vertical extension of the mandible; it doesn't specifically denote the angle formed with the body. The nasal cavity and the hard palate are structures located in different regions of the skull and do not relate to the angle formed by the ramus and body of the mandible. Understanding the anatomy of the mandible, especially its angles and ramus, is crucial for professionals in dental nursing and related fields.