What is true of synovial joints? They:

Correct Answer: C

Rationale: Synovial joints have a fluid-filled cavity (synovial fluid), not discs in all, and aren’t amphiarthroses or cartilaginous. Answer is C, per the document.

Correct Answer: B

Rationale: The occipital bone forms the cranium’s base, not a carpal, vertebra, or facial bone. Answer is B, per the document.

Correct Answer: D

Rationale: The skull houses and protects sense organs (e.g., eyes in orbits, ears in temporal bones) alongside the brain. Lungs and diaphragm are thoracic, cells are everywhere—not skull-protected—making 'the sense organs' correct.

Correct Answer: D

Rationale: Muscles consist of fibres (elongated cells) bundled together, enabling contraction. Silica is in trace amounts, polyester is synthetic, calcium/phosphorus are bone minerals, making 'groups of cells called fibres' correct.

Correct Answer: D

Rationale: A facet is a flat or shallow surface on a bone where articulation occurs, such as in vertebral joints. A tubercle is a small projection, a fossa is a depression, and a fovea is a small pit—none describe a shallow articulating surface as precisely as facet.