Final answer:
The superior and middle nasal conchae are projections of the C) ethmoid bone, as opposed to the inferior concha, which is a separate bone.
Step-by-step explanation:
The student has asked about the projections known as nasal conchae within the nasal cavity of the skull.
The inferior nasal concha is a separate bone, whereas the superior and middle nasal conchae are both projections of the C) ethmoid bone.
This can be observed by looking at the lateral wall of the nasal cavity, where these bony plates are visible as they curve downward into the space of the nasal cavity.
They serve various functions, including warming, moisturizing incoming air, and trapping debris through mucus.