The terms "occipital," "parietal," and "frontal" can refer collectively to which part of the body?

The cranium

Explanation:

The cranium is the upper part of the skull that is made up of eight bones that do not move, which serves as protection for the delicate brain structure in humans. The cranium bones are named according to the area of the brain they serve as protection to these are: the sphenoid bone, the ethmoid bone, the occipital bone, the two temporal bones, the frontal bone, and the two parietal bones, making eight in number.

The occipital bone protects the occipital lobe; the parietal bones protects the parietal lobe of the brain; and the frontal bone protects the frontal lobe of the brain.