Final answer:
The correct answer is suture joint, which is a type of fibrous joint that connects the bones of the skull.
Step-by-step explanation:
A fibrous joint functions to strongly unite adjacent bones, providing protection and stability. The options given are: a) Synovial joint, b) Cartilaginous joint, c) Suture joint, and d) Symphysis joint. Among these options, the correct answer is c) Suture joint, as it is a type of fibrous joint that connects the bones of the skull.