Final answer:
The bone labeled "C" in the context of a skull diagram is likely the zygomatic bone, also known as the cheekbone, which contributes to the zygomatic arch.
Step-by-step explanation:
The bone of the skull labeled "C" is likely to be the zygomatic bone, which is also known as the cheekbone. This bone forms much of the lateral wall of the orbit and the lateral-inferior margins of the anterior orbital opening.
The zygomatic bone includes the temporal process that forms the anterior portion of the zygomatic arch, which is the bony arch on the side of the skull that spans from the area of the cheek to just above the ear canal.