Which of the following is a characteristic of the parietal bone?

The characteristic of the parietal bone being part of the skull is correct because the parietal bones are two large, curved bones located on the top and sides of the skull in humans. They form a significant portion of the cranial vault, which is essential for both structure and protection of the brain.

While other options refer to important parts of the skeletal system, they do not accurately describe the parietal bone itself. The option concerning the forehead refers to the frontal bone, which is separate and distinct from the parietal. Encasing the brain pertains more broadly to the entire cranial structure rather than specifically to the parietal bones. The option that discusses protection of the eyes relates to the bones of the orbit, which do not include the parietal bone. Thus, identifying the parietal bone as part of the skull is a defining and accurate characteristic.