Which bone structure supports the teeth in the upper jaw?

The maxilla is the correct answer because it is the upper jawbone and plays a vital role in supporting the upper teeth. This bone houses the sockets for the upper teeth (dental alveoli) and forms a crucial part of both the facial skeleton and the oral cavity.

In addition to providing support for the upper teeth, the maxilla also participates in the formation of the orbits of the eyes and the nasal cavity. Its structure is essential for proper occlusion and alignment of the upper teeth, making it crucial for overall dental health and function.

Other options do not serve this function. The mandible is the lower jawbone, which does support the lower teeth but not the upper ones. The maxillary sinus is an air-filled space within the maxilla that can affect dental health but does not support teeth. The nasal bone contributes to the structure of the nose but has no direct role in supporting teeth.