Question

the cranial bone that is completely enclosed or surrounded is the ____ bone.
ethmoid
sphenoid
temporal
parietal

Explanation:

The ethmoid bone is located deep within the cranial cavity, completely surrounded by other cranial bones (frontal, sphenoid, temporal, and occipital bones). The sphenoid, temporal, and parietal bones all have exposed surfaces on the exterior of the skull, so they are not fully enclosed.

Answer:

ethmoid