The cranial bones are part of the skull, and they protect the brain. Among the given options:
- Occipital is a cranial bone located at the back of the skull and is directly involved in enclosing the brain.
- Mandible is the lower jawbone and is not a cranial bone; it's a facial bone.
- Coccyx is the tailbone, not part of the skull.
- Sternum is the breastbone, located in the chest, and is also not a cranial bone.
Thus, the correct answer is (A) Occipital, a cranial bone.
Final Answer: (A)