Which joint is most likely to be dislocated?

Rationale:
A. Melanin production protects against ultraviolet (UV) radiation but does not directly prevent bacterial entry.
B. Sensory perception allows detection of touch, pressure, pain, and temperature, but it does not serve as a barrier against pathogens.
C. The skin acts as a physical and chemical barrier, preventing bacteria, viruses, and other pathogens from entering the body. Its intact epidermis, along with secretions such as sweat and sebum, helps maintain this protective function.
D. Filtration is a function associated with organs like the kidneys, not the skin.

Rationale:
A. Amphiarthroses are slightly movable joints where bones are connected by cartilage. Examples include the intervertebral discs (between vertebrae) and the pubic symphysis. These joints allow limited movement while providing strength and stability.
B. These are freely movable joints, also known as synovial joints (such as the knee, elbow, and shoulder). They are not primarily joined by cartilage but by a synovial cavity and ligaments.
C. These are immovable joints where bones are connected by fibrous tissue, such as the sutures of the skull. They do not involve cartilage.
D. A type of diarthrosis characterized by a synovial cavity filled with fluid, articular cartilage, and supporting ligaments, allowing free movement. They are not defined solely by cartilage connections.